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Hi there, Isn't anybody can provide me the method to convert the a2d output (from floating point binary data) to Ascii , so i can sent the ascii code output to SCI/terminal . Thank you

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In a message dated 12/25/02 8:36:09 AM Eastern Standard Time, writes: > Isn't anybody can provide me the method to convert the a2d output > (from floating point binary data) to Ascii , so i can sent the ascii > code output to SCI/terminal . Thank you unsigned char addat; float volts; addat=readadchan(); //read a/d volts=addat*5.0/255.0; //convert to floating point printf("%7.3f\n"); //print out sci terminal [Non-text portions of this message have been removed]

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--- In , BobGardner@a... wrote: > In a message dated 12/25/02 8:36:09 AM Eastern Standard Time, > liewbw@m... writes: > > > Isn't anybody can provide me the method to convert the a2d output > > (from floating point binary data) to Ascii , so i can sent the ascii > > code output to SCI/terminal . Thank you > > > > unsigned char addat; > float volts; > > addat=readadchan(); //read a/d > volts=addat*5.0/255.0; //convert to floating point > printf("%7.3f\n"); //print out sci terminal > May i have the example code in asembly format ? thank you > [Non-text portions of this message have been removed]

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In a message dated 12/25/02 12:31:21 PM Eastern Standard Time, writes: > >unsigned char addat; > >float volts; > > > >addat=readadchan(); //read a/d > >volts=addat*5.0/255.0; //convert to floating point > >printf("%7.3f\n"); //print out sci terminal Life's too short to remember which variable is in which register. If you really have to see what the assembly looks like, dl the imagecraft compiler, compile it, then look at the compiler generated assembly language..... I can't imagine anything needing assembler anymore... that's right you guys... a challenge... bring it on... send the spec and your tightest assembly code... [Non-text portions of this message have been removed]

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--- In , BobGardner@a... wrote: > In a message dated 12/25/02 12:31:21 PM Eastern Standard Time, > liewbw@m... writes: > > > >unsigned char addat; > > >float volts; > > > > > >addat=readadchan(); //read a/d > > >volts=addat*5.0/255.0; //convert to floating point > > >printf("%7.3f\n"); //print out sci terminal > > > > Life's too short to remember which variable is in which register. If you > really have to see what the assembly looks like, dl the imagecraft compiler, > compile it, then look at the compiler generated assembly language..... I > can't imagine anything needing assembler anymore... that's right you guys... > a challenge... bring it on... send the spec and your tightest assembly > code... > [Non-text portions of this message have been removed] Herer is my project run Sensor --> MC68HC11 (A2D) ---> RS232 ---> Computer Below is the part of the asembly code for link the measured out to port E : *===================================================================== * Init A2D: Initialize the Analog to Digital convertor *===================================================================== INIT_A2D: LDX #$1000 ; needed for the BRCLR command LDAA #%10010000 ; Power up A/D with clock delay STAA $39,x RTS *===================================================================== * Read A2D values: *===================================================================== Read_A2D: LDAA #%00000000 ; single scan, multi-mode, pins e0-3 STAA $30,x ; WRITE staRTS conversion CONVERSION_NOT_DONE BRCLR $30,x $80 CONVERSION_NOT_DONE LDAA $31,x ; GET VALUE FORM PIN PE0 PULX RTS *===================================================================== * WRITE A2D: WRITE the 8 A2D values in Ram to the TERMinal. *===================================================================== WRITE_A2D: LDAA A2D0 LDAB #'0 BSR WRITE_A2D_BYTE LDAA A2D1 INCB BSR WRITE_A2D_BYTE LDAA A2D2 INCB BSR WRITE_A2D_BYTE LDAA A2D3 INCB BSR WRITE_A2D_BYTE LDAA A2D4 INCB BSR WRITE_A2D_BYTE LDAA A2D5 INCB BSR WRITE_A2D_BYTE LDAA A2D6 INCB BSR WRITE_A2D_BYTE LDAA A2D7 INCB BSR WRITE_A2D_BYTE RTS WRITE_A2D_BYTE: psha pshb BSR WRITE_TERM LDAB #': BSR WRITE_TERM TAB lsrb lsrb lsrb lsrb LDY #WA2D_TABle ; 4-bits to HEX aby LDAB $00,y BSR WRITE_TERM TAB andb #$0F LDY #WA2D_TABle aby LDAB $00,y JSR WRITE_TERM LDAB #$20 ; Space JSR WRITE_TERM pulb pula RTS WA2D_TABle: fcc "0123456789ABCDEF" *===================================================================== * WRITE 2 TERMinal: * Input: ASCII data in the B register. * Action: Wait until transmit buffer is empty, then * transmit the data in the B register. *===================================================================== WRITE_TERM: BRCLR $2e,x %10000000 WRITE_TERM ; check Transmit-empty STAB $2f,x RTS ============================================== What i have done is convert the analog measurement data and sent to Port PE0 for conversion. The Voltage reference is 5 V for high and 0 v for low.So, how to take the converted data from A2D result and shift into a 8 bit binary data and then convert to ascii code . The ascii code will transmit to SCI port.Thank you

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Why convert it to flotating point in the first place. Read the A/D register as a short, int or long as approiate and and send it as is. If you are going to use it on an Intel or other machine you will have to reverse the byte in the case of an int and I don't rember how to handle a long. If you don't need floating point don't link it in. It is SLOOOOOOW. I woked whith a 68HC11 for 7 years professionaly and never had to use floating point. I had to use some awkward fractions and such but I never could afford the speed loss that F.P. cost. I printed them out in hex on a termial because they were 8 bit A/C converers and hex kept them in orderly rows. I used somting like witten from memory the sentax may not be correct but you should get the idea.. char *hexstr ="0123456789ABCDEF" void print-hex(char a) { char [3] s; s[2] =0; s[0]=hex-str[ a%16]; /* mod 16 I may have the operater wrong and the order reversed */ s[1]=hex-str[a/16]; puts(s); } It's crude but small and fast and the string s was often a pointer to a global string that I have for an output line insted of a local variable. Again not clean but fast and small. Gordon Gordon Couger Stillwater, OK www.couger.com/gcouger ----- Original Message ----- From: <> To: <> Sent: Wednesday, December 25, 2002 9:55 AM Subject: [m68HC11] Re: A2D binary to Ascii conversion to terminal > --- In , BobGardner@a... wrote: > > In a message dated 12/25/02 12:31:21 PM Eastern Standard Time, > > liewbw@m... writes: > > > > > >unsigned char addat; > > > >float volts; > > > > > > > >addat=readadchan(); //read a/d > > > >volts=addat*5.0/255.0; //convert to floating point > > > >printf("%7.3f\n"); //print out sci terminal > > > > > > > Life's too short to remember which variable is in which register. > If you > > really have to see what the assembly looks like, dl the imagecraft > compiler, > > compile it, then look at the compiler generated assembly > language..... I > > can't imagine anything needing assembler anymore... that's right > you guys... > > a challenge... bring it on... send the spec and your tightest > assembly > > code... > > > > > > [Non-text portions of this message have been removed] > > > Herer is my project run > > Sensor --> MC68HC11 (A2D) ---> RS232 ---> Computer > Below is the part of the asembly code for link the measured out to > port E : > > *===================================================================== > * Init A2D: Initialize the Analog to Digital convertor > *===================================================================== > INIT_A2D: > LDX #$1000 ; needed for the BRCLR command > LDAA #%10010000 ; Power up A/D with clock delay > STAA $39,x > RTS > *===================================================================== > * Read A2D values: > *===================================================================== > Read_A2D: > LDAA #%00000000 ; single scan, multi-mode, pins e0-3 > STAA $30,x ; WRITE staRTS conversion > > CONVERSION_NOT_DONE > BRCLR $30,x $80 CONVERSION_NOT_DONE > LDAA $31,x ; GET VALUE FORM PIN PE0 > PULX > RTS > *===================================================================== > * WRITE A2D: WRITE the 8 A2D values in Ram to the TERMinal. > *===================================================================== > WRITE_A2D: > LDAA A2D0 > LDAB #'0 > BSR WRITE_A2D_BYTE > LDAA A2D1 > INCB > BSR WRITE_A2D_BYTE > LDAA A2D2 > INCB > BSR WRITE_A2D_BYTE > LDAA A2D3 > INCB > BSR WRITE_A2D_BYTE > LDAA A2D4 > INCB > BSR WRITE_A2D_BYTE > LDAA A2D5 > INCB > BSR WRITE_A2D_BYTE > LDAA A2D6 > INCB > BSR WRITE_A2D_BYTE > LDAA A2D7 > INCB > BSR WRITE_A2D_BYTE > RTS > > WRITE_A2D_BYTE: > psha > pshb > BSR WRITE_TERM > LDAB #': > BSR WRITE_TERM > TAB > lsrb > lsrb > lsrb > lsrb > LDY #WA2D_TABle ; 4-bits to HEX > aby > LDAB $00,y > BSR WRITE_TERM > TAB > andb #$0F > LDY #WA2D_TABle > aby > LDAB $00,y > JSR WRITE_TERM > LDAB #$20 ; Space > JSR WRITE_TERM > pulb > pula > RTS > WA2D_TABle: > fcc "0123456789ABCDEF" > > *===================================================================== > * WRITE 2 TERMinal: > * Input: ASCII data in the B register. > * Action: Wait until transmit buffer is empty, then > * transmit the data in the B register. > *===================================================================== > WRITE_TERM: > BRCLR $2e,x %10000000 WRITE_TERM ; check Transmit-empty > STAB $2f,x > RTS > > > ============================================== > What i have done is convert the analog measurement data and sent to > Port PE0 for conversion. The Voltage reference is 5 V for high and 0 > v for low.So, how to take the converted data from A2D result and > shift into a 8 bit binary data and then convert to ascii code . The > ascii code will transmit to SCI port.Thank you > To unsubscribe from this group, send an email to:

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Hi , Thanks for giving me the advice. Since i am still a beginner for MC68HC11,i hope sir can give me some advice for this problem.I am using MC68HC11A0P F92J for the project in expanded mode .As i know , the A2D results will store into ADR1-ADR4 register ($1031 to $1034).Isnt each register just hold 2 bit data ? Does i need to combine each register (ADR1 + ADR2+ ADR3 +ADR4 = 8 bit binary data) and keep as 8 bit binary data . May i know that what is the meaning of " MC68HC11 Floating Point Package" ? software code or hardware? If the measured analog data is 3.58 V(V max = 5V) , isnt the 6811 A2D will automaticlly convert it as a floating point binary output or just a decimal output only ?Since the RS232 just accept Ascii code, so how can i convert the A2D result to ASCII code ( let said 3.58 in ascii code format),I hope sir can show me the example in asembly code for me .Thank you ----- Original Message ----- From: Gordon Couger To: Sent: Thursday, December 26, 2002 3:09 PM Subject: Re: [m68HC11] Re: A2D binary to Ascii conversion to terminal Why convert it to flotating point in the first place. Read the A/D register as a short, int or long as approiate and and send it as is. If you are going to use it on an Intel or other machine you will have to reverse the byte in the case of an int and I don't rember how to handle a long. If you don't need floating point don't link it in. It is SLOOOOOOW. I woked whith a 68HC11 for 7 years professionaly and never had to use floating point. I had to use some awkward fractions and such but I never could afford the speed loss that F.P. cost. I printed them out in hex on a termial because they were 8 bit A/C converers and hex kept them in orderly rows. I used somting like witten from memory the sentax may not be correct but you should get the idea.. char *hexstr ="0123456789ABCDEF" void print-hex(char a) { char [3] s; s[2] =0; s[0]=hex-str[ a%16]; /* mod 16 I may have the operater wrong and the order reversed */ s[1]=hex-str[a/16]; puts(s); } It's crude but small and fast and the string s was often a pointer to a global string that I have for an output line insted of a local variable. Again not clean but fast and small. Gordon Gordon Couger Stillwater, OK www.couger.com/gcouger ----- Original Message ----- From: <> To: <> Sent: Wednesday, December 25, 2002 9:55 AM Subject: [m68HC11] Re: A2D binary to Ascii conversion to terminal > --- In , BobGardner@a... wrote: > > In a message dated 12/25/02 12:31:21 PM Eastern Standard Time, > > liewbw@m... writes: > > > > > >unsigned char addat; > > > >float volts; > > > > > > > >addat=readadchan(); //read a/d > > > >volts=addat*5.0/255.0; //convert to floating point > > > >printf("%7.3f\n"); //print out sci terminal > > > > > > > Life's too short to remember which variable is in which register. > If you > > really have to see what the assembly looks like, dl the imagecraft > compiler, > > compile it, then look at the compiler generated assembly > language..... I > > can't imagine anything needing assembler anymore... that's right > you guys... > > a challenge... bring it on... send the spec and your tightest > assembly > > code... > > > > > > [Non-text portions of this message have been removed] > > > Herer is my project run > > Sensor --> MC68HC11 (A2D) ---> RS232 ---> Computer > Below is the part of the asembly code for link the measured out to > port E : > > *===================================================================== > * Init A2D: Initialize the Analog to Digital convertor > *===================================================================== > INIT_A2D: > LDX #$1000 ; needed for the BRCLR command > LDAA #%10010000 ; Power up A/D with clock delay > STAA $39,x > RTS > *===================================================================== > * Read A2D values: > *===================================================================== > Read_A2D: > LDAA #%00000000 ; single scan, multi-mode, pins e0-3 > STAA $30,x ; WRITE staRTS conversion > > CONVERSION_NOT_DONE > BRCLR $30,x $80 CONVERSION_NOT_DONE > LDAA $31,x ; GET VALUE FORM PIN PE0 > PULX > RTS > *===================================================================== > * WRITE A2D: WRITE the 8 A2D values in Ram to the TERMinal. > *===================================================================== > WRITE_A2D: > LDAA A2D0 > LDAB #'0 > BSR WRITE_A2D_BYTE > LDAA A2D1 > INCB > BSR WRITE_A2D_BYTE > LDAA A2D2 > INCB > BSR WRITE_A2D_BYTE > LDAA A2D3 > INCB > BSR WRITE_A2D_BYTE > LDAA A2D4 > INCB > BSR WRITE_A2D_BYTE > LDAA A2D5 > INCB > BSR WRITE_A2D_BYTE > LDAA A2D6 > INCB > BSR WRITE_A2D_BYTE > LDAA A2D7 > INCB > BSR WRITE_A2D_BYTE > RTS > > WRITE_A2D_BYTE: > psha > pshb > BSR WRITE_TERM > LDAB #': > BSR WRITE_TERM > TAB > lsrb > lsrb > lsrb > lsrb > LDY #WA2D_TABle ; 4-bits to HEX > aby > LDAB $00,y > BSR WRITE_TERM > TAB > andb #$0F > LDY #WA2D_TABle > aby > LDAB $00,y > JSR WRITE_TERM > LDAB #$20 ; Space > JSR WRITE_TERM > pulb > pula > RTS > WA2D_TABle: > fcc "0123456789ABCDEF" > > *===================================================================== > * WRITE 2 TERMinal: > * Input: ASCII data in the B register. > * Action: Wait until transmit buffer is empty, then > * transmit the data in the B register. > *===================================================================== > WRITE_TERM: > BRCLR $2e,x %10000000 WRITE_TERM ; check Transmit-empty > STAB $2f,x > RTS > > > ============================================== > What i have done is convert the analog measurement data and sent to > Port PE0 for conversion. The Voltage reference is 5 V for high and 0 > v for low.So, how to take the converted data from A2D result and > shift into a 8 bit binary data and then convert to ascii code . The > ascii code will transmit to SCI port.Thank you > To unsubscribe from this group, send an email to: To unsubscribe from this group, send an email to: Your use of Yahoo! Groups is subject to the Yahoo! Terms of Service. [Non-text portions of this message have been removed]

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In a message dated 12/26/02 5:36:31 AM Eastern Standard Time, writes: > .As i know , the A2D results will store into ADR1-ADR4 register ($1031 to > $1034).Isnt each register just hold 2 bit data ? Does i need to combine > each register (ADR1 + ADR2+ ADR3 +ADR4 = 8 bit binary data) and keep as 8 > bit binary data . May i know that what is the meaning of " MC68HC11 > Floating Point Package" ? software code or hardware? If the measured analog > data is 3.58 V(V max = 5V) , isnt the 6811 A2D will automaticlly convert it > as a floating point binary output or just a decimal output only ?Since the > RS232 just accept Ascii code, so how can i convert the A2D result to ASCII > code ( let said 3.58 in ascii code format),I hope sir can show me the > example in asembly code for me .Thank you Each register holds an 8 bit byte...one a/d conversion result. There are 8 channels on the multiplexer.... you can read 8 different analog voltages. The Floating Point Package is a subroutine library to do single precision floating point in software...Many would say this is unnecessary... the same computations can be done using integer arithmetic... the a/d converter just gives an 8 bit result 0 to 255... if you need this in volts, you must call the floating point routines to convert the integer to ploating point, call the floating point multiply/add/divide routines as needed.... all this detail is tedious in assembler... rather than spend days learning all this low level stuff, spend a couple days learning to compile and burn some one page c programs... you'll be more productive in the long run.... [Non-text portions of this message have been removed]

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So it mean if I just use 1 channel (PE0) for analog input only, so i just need to take the ADR1 register output only ,then convert it to ascii code.below is the floating point conversion code example. After i take the output from register ADR1, i move the data to the fp routine, it will display output as ASCii, right ? ****************************************************************************** * FLOATING POINT TO ASCII CONVERSION SUBROUTINE * * This subroutine performs floating point to ASCII conversion of * * the number in FPACC1. The ascii string is placed in a buffer * * pointed to by the X index register. The buffer must be at least * * 14 bytes long to contain the ASCII conversion. The resulting * * ASCII string is terminated by a zero (0) byte. Upon exit the * * X Index register will be pointing to the first character of the * * string. FPACC1 and FPACC2 will remain unchanged. * ****************************************************************************** FLTASC EQU * PSHX SAVE THE POINTER TO THE STRING BUFFER. LDX #FPACC1EX POINT TO FPACC1. JSR CHCK0 IS FPACC1 0? BNE FLTASC1 NO. GO CONVERT THE NUMBER. PULX RESTORE POINTER. LDD #$3000 GET ASCII CHARACTER + TERMINATING BYTE. STD 0,X PUT IT IN THE BUFFER. RTS RETURN. FLTASC1 LDX FPACC1EX SAVE FPACC1. PSHX LDX FPACC1MN+1 PSHX LDAA MANTSGN1 PSHA JSR PSHFPAC2 SAVE FPACC2. LDX #0 PSHX ALLOCATE LOCALS. PSHX PSHX SAVE SPACE FOR STRING BUFFER POINTER. TSY POINT TO LOCALS. LDX 15,Y GET POINTER FROM STACK. LDAA #$20 PUT A SPACE IN THE BUFFER IF NUMBER NOT NEGATIVE. TST MANTSGN1 IS IT NEGATIVE? BEQ FLTASC2 NO. GO PUT SPACE. CLR MANTSGN1 MAKE NUMBER POSITIVE FOR REST OF CONVERSION. LDAA #'- YES. PUT MINUS SIGN IN BUFFER. FLTASC2 STAA 0,X INX POINT TO NEXT LOCATION. STX 0,Y SAVE POINTER. FLTASC5 LDX #N9999999 POINT TO CONSTANT 9999999. JSR GETFPAC2 GET INTO FPACC2. JSR FLTCMP COMPARE THE NUMBERS. IS FPACC1 > 9999999? BHI FLTASC3 YES. GO DIVIDE FPACC1 BY 10. LDX #P9999999 POINT TO CONSTANT 999999.9 JSR GETFPAC2 MOVE IT INTO FPACC2. JSR FLTCMP COMPARE NUMBERS. IS FPACC1 > 999999.9? BHI FLTASC4 YES. GO CONTINUE THE CONVERSION. DEC 2,Y DECREMENT THE MULT./DIV. COUNT. LDX #CONST10 NO. MULTIPLY BY 10. POINT TO CONSTANT. FLTASC6 JSR GETFPAC2 MOVE IT INTO FPACC2. JSR FLTMUL BRA FLTASC5 GO DO COMPARE AGAIN. FLTASC3 INC 2,Y INCREMENT THE MULT./DIV. COUNT. LDX #CONSTP1 POINT TO CONSTANT ".1". BRA FLTASC6 GO DIVIDE FPACC1 BY 10. FLTASC4 LDX #CONSTP5 POINT TO CONSTANT OF ".5". JSR GETFPAC2 MOVE IT INTO FPACC2. JSR FLTADD ADD .5 TO NUMBER IN FPACC1 TO ROUND IT. LDAB FPACC1EX GET FPACC1 EXPONENT. SUBB #$81 TAKE OUT BIAS +1. NEGB MAKE IT NEGATIVE. ADDB #23 ADD IN THE NUMBER OF MANTISSA BITS -1. BRA FLTASC17 GO CHECK TO SEE IF WE NEED TO SHIFT AT ALL. FLTASC7 LSR FPACC1MN SHIFT MANTISSA TO THE RIGHT BY THE RESULT (MAKE ROR FPACC1MN+1 THE NUMBER AN INTEGER). ROR FPACC1MN+2 DECB DONE SHIFTING? FLTASC17 BNE FLTASC7 NO. KEEP GOING. LDAA #1 GET INITIAL VALUE OF "DIGITS AFTER D.P." COUNT. STAA 3,Y INITIALIZE IT. LDAA 2,Y GET DECIMAL EXPONENT. ADDA #8 ADD THE NUMBER OF DECIMAL +1 TO THE EXPONENT. * WAS THE ORIGINAL NUMBER > 9999999? BMI FLTASC8 YES. MUST BE REPRESENTED IN SCIENTIFIC NOTATION. CMPA #8 WAS THE ORIGINAL NUMBER < 1? BHS FLTASC8 YES. MUST BE REPRESENTED IN SCIENTIFIC NOTATION. DECA NO. NUMBER CAN BE REPRESENTED IN 7 DIGITS. STAA 3,Y MAKE THE DECIMAL EXPONENT THE DIGIT COUNT BEFORE * THE DECIMAL POINT. LDAA #2 SETUP TO ZERO THE DECIMAL EXPONENT. FLTASC8 SUBA #2 SUBTRACT 2 FROM THE DECIMAL EXPONENT. STAA 2,Y SAVE THE DECIMAL EXPONENT. TST 3,Y DOES THE NUMBER HAVE AN INTEGER PART? (EXP. >0) BGT FLTASC9 YES. GO PUT IT OUT.9 LDAA #'. NO. GET DECIMAL POINT. LDX 0,Y GET POINTER TO BUFFER. STAA 0,X PUT THE DECIMAL POINT IN THE BUFFER. INX POINT TO NEXT BUFFER LOCATION. TST 3,Y IS THE DIGIT COUNT TILL EXPONENT =0? BEQ FLTASC18 NO. NUMBER IS <.1 LDAA #'0 YES. FORMAT NUMBER AS .0XXXXXXX STAA 0,X PUT THE 0 IN THE BUFFER. INX POINT TO THE NEXT LOCATION. FLTASC18 STX 0,Y SAVE NEW POINTER VALUE. FLTASC9 LDX #DECDIG POINT TO THE TABLE OF DECIMAL DIGITS. LDAA #7 INITIALIZE THE THE NUMBER OF DIGITS COUNT. STAA 5,Y FLTASC10 CLR 4,Y CLEAR THE DECIMAL DIGIT ACCUMULATOR. FLTASC11 LDD FPACC1MN+1 GET LOWER 16 BITS OF MANTISSA. SUBD 1,X SUBTRACT LOWER 16 BITS OF CONSTANT. STD FPACC1MN+1 SAVE RESULT. LDAA FPACC1MN GET UPPER 8 BITS. SBCA 0,X SUBTRACT UPPER 8 BITS. STAA FPACC1MN SAVE RESULT. UNDERFLOW? BCS FLTASC12 YES. GO ADD DECIMAL NUMBER BACK IN. INC 4,Y ADD 1 TO DECIMAL NUMBER. BRA FLTASC11 TRY ANOTHER SUBTRACTION. FLTASC12 LDD FPACC1MN+1 GET FPACC1 MANTISSA LOW 16 BITS. ADDD 1,X ADD LOW 16 BITS BACK IN. STD FPACC1MN+1 SAVE THE RESULT. LDAA FPACC1MN GET HIGH 8 BITS. ADCA 0,X ADD IN HIGH 8 BITS OF CONSTANT. STAA FPACC1MN SAVE RESULT. LDAA 4,Y GET DIGIT. ADDA #$30 MAKE IT ASCII. PSHX SAVE POINTER TO CONSTANTS. LDX 0,Y GET POINTER TO BUFFER. STAA 0,X PUT DIGIT IN BUFFER. INX POINT TO NEXT BUFFER LOCATION. DEC 3,Y SHOULD WE PUT A DECIMAL POINT IN THE BUFFER YET? BNE FLTASC16 NO. CONTINUE THE CONVERSION. LDAA #'. YES. GET DECIMAL POINT. STAA 0,X PUT IT IN THE BUFFER. INX POINT TO THE NEXT BUFFER LOCATION. FLTASC16 STX 0,Y SAVE UPDATED POINTER. PULX RESTORE POINTER TO CONSTANTS. INX POINT TO NEXT CONSTANT. INX INX DEC 5,Y DONE YET? BNE FLTASC10 NO. CONTINUE CONVERSION OF "MANTISSA". LDX 0,Y YES. POINT TO BUFFER STRING BUFFER. FLTASC13 DEX POINT TO LAST CHARACTER PUT IN THE BUFFER. LDAA 0,X GET IT. CMPA #$30 WAS IT AN ASCII 0? BEQ FLTASC13 YES. REMOVE TRAILING ZEROS. INX POINT TO NEXT AVAILABLE LOCATION IN BUFFER. LDAB 2,Y DO WE NEED TO PUT OUT AN EXPONENT? BEQ FLTASC15 NO. WE'RE DONE. LDAA #'E YES. PUT AN 'E' IN THE BUFFER. STAA 0,X INX POINT TO NEXT BUFFER LOCATION. LDAA #'+ ASSUME EXPONENT IS POSITIVE. STAA 0,X PUT PLUS SIGN IN THE BUFFER. TSTB IS IT REALLY MINUS? BPL FLTASC14 NO. IS'S OK AS IS. NEGB YES. MAKE IT POSITIVE. LDAA #'- PUT THE MINUS SIGN IN THE BUFFER. STAA 0,X FLTASC14 INX POINT TO NEXT BUFFER LOCATION. STX 0,Y SAVE POINTER TO STRING BUFFER. CLRA SET UP FOR DIVIDE. LDX #10 DIVIDE DECIMAL EXPONENT BY 10. IDIV PSHB SAVE REMAINDER. XGDX PUT QUOTIENT IN D. ADDB #$30 MAKE IT ASCII. LDX 0,Y GET POINTER. STAB 0,X PUT NUMBER IN BUFFER. INX POINT TO NEXT LOCATION. PULB GET SECOND DIGIT. ADDB #$30 MAKE IT ASCII. STAB 0,X PUT IT IN THE BUFFER. INX POINT TO NEXT LOCATION. FLTASC15 CLR 0,X TERMINATE STRING WITH A ZERO BYTE. PULX CLEAR LOCALS FROM STACK. PULX PULX JSR PULFPAC2 RESTORE FPACC2. PULA STAA MANTSGN1 PULX RESTORE FPACC1. STX FPACC1MN+1 PULX STX FPACC1EX PULX POINT TO THE START OF THE ASCII STRING. RTS RETURN. * * DECDIG EQU * FCB $0F,$42,$40 DECIMAL 1,000,000 FCB $01,$86,$A0 DECIMAL 100,000 FCB $00,$27,$10 DECIMAL 10,000 FCB $00,$03,$E8 DECIMAL 1,000 FCB $00,$00,$64 DECIMAL 100 FCB $00,$00,$0A DECIMAL 10 FCB $00,$00,$01 DECIMAL 1 * * P9999999 EQU * CONSTANT 999999.9 FCB $94,$74,$23,$FE * N9999999 EQU * CONSTANT 9999999. FCB $98,$18,$96,$7F * CONSTP5 EQU * CONSTANT .5 FCB $80,$00,$00,$00 * * FLTCMP EQU * TST MANTSGN1 IS FPACC1 NEGATIVE? BPL FLTCMP2 NO. CONTINUE WITH COMPARE. TST MANTSGN2 IS FPACC2 NEGATIVE? BPL FLTCMP2 NO. CONTINUE WITH COMPARE. LDD FPACC2EX YES. BOTH ARE NEGATIVE SO COMPARE MUST BE DONE CPD FPACC1EX BACKWARDS. ARE THEY EQUAL SO FAR? BNE FLTCMP1 NO. RETURN WITH CONDITION CODES SET. LDD FPACC2MN+1 YES. COMPARE LOWER 16 BITS OF MANTISSAS. CPD FPACC1MN+1 FLTCMP1 RTS RETURN WITH CONDITION CODES SET. FLTCMP2 LDAA MANTSGN1 GET FPACC1 MANTISSA SIGN. CMPA MANTSGN2 BOTH POSITIVE? BNE FLTCMP1 NO. RETURN WITH CONDITION CODES SET. LDD FPACC1EX GET FPACC1 EXPONENT & UPPER 8 BITS OF MANTISSA. CPD FPACC2EX SAME AS FPACC2? BNE FLTCMP1 NO. RETURN WITH CONDITION CODES SET. LDD FPACC1MN+1 GET FPACC1 LOWER 16 BITS OF MANTISSA. CPD FPACC2MN+1 COMPARE WITH FPACC2 LOWER 16 BITS OF MANTISSA. RTS RETURN WITH CONDITION CODES SET. * * * TTL INT2FLT ----- Original Message ----- From: To: Sent: Thursday, December 26, 2002 8:56 PM Subject: Re: [m68HC11] Re: A2D binary to Ascii conversion to terminal In a message dated 12/26/02 5:36:31 AM Eastern Standard Time, writes: > .As i know , the A2D results will store into ADR1-ADR4 register ($1031 to > $1034).Isnt each register just hold 2 bit data ? Does i need to combine > each register (ADR1 + ADR2+ ADR3 +ADR4 = 8 bit binary data) and keep as 8 > bit binary data . May i know that what is the meaning of " MC68HC11 > Floating Point Package" ? software code or hardware? If the measured analog > data is 3.58 V(V max = 5V) , isnt the 6811 A2D will automaticlly convert it > as a floating point binary output or just a decimal output only ?Since the > RS232 just accept Ascii code, so how can i convert the A2D result to ASCII > code ( let said 3.58 in ascii code format),I hope sir can show me the > example in asembly code for me .Thank you Each register holds an 8 bit byte...one a/d conversion result. There are 8 channels on the multiplexer.... you can read 8 different analog voltages. The Floating Point Package is a subroutine library to do single precision floating point in software...Many would say this is unnecessary... the same computations can be done using integer arithmetic... the a/d converter just gives an 8 bit result 0 to 255... if you need this in volts, you must call the floating point routines to convert the integer to ploating point, call the floating point multiply/add/divide routines as needed.... all this detail is tedious in assembler... rather than spend days learning all this low level stuff, spend a couple days learning to compile and burn some one page c programs... you'll be more productive in the long run.... [Non-text portions of this message have been removed] To unsubscribe from this group, send an email to: Your use of Yahoo! Groups is subject to the Yahoo! Terms of Service. [Non-text portions of this message have been removed]

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I have been watching this thread with interest and have become concerned that the author has been exposed to some serious misunderstandings with regard to the operation of the 'HC11 A/D Converter Subsystem, 'HC11 data formats, and the operation of RS-232 serial data systems in general. Below, I will inject some comments intended to help him with his project. Bob Smith --- Avoid computer viruses, Practice safe hex --- -- Specializing in small, cost effective embedded control systems -- Robert L. (Bob) Smith Smith Machine Works, Inc. 9900 Lumlay Road Richmond, VA 23236 804/745-1065 ----- Original Message ----- From: "Liew Ban Wui" <> To: <> Cc: <> Sent: Thursday, December 26, 2002 5:29 AM Subject: Re: [m68HC11] Re: A2D binary to Ascii conversion to terminal > Hi , > Thanks for giving me the advice. Since i am still a beginner for MC68HC11,i hope sir can give me some advice for this problem.I am using MC68HC11A0P F92J for the project in expanded mode . This does not seem like a familiar 'HC11A0 part number, particularily the "PF92J" part of it. Since it seems to be an 'A0' part, I will proceed on that basis. BUT, WARNING, the 'A0 family has been obsoleted by Motorola and is in short supply. I recommend immediate conversion to the E family devices. Motorola has an Engineering Bullentin on A to E family conversion considerations at the web site. As i know , the A2D results will store into ADR1-ADR4 register ($1031 to $1034).Isnt each register just hold 2 bit data ? Major misconception! Each A/D result register returns an 8 bit unsigned binary number (In the range of $00 to $FF). The result returned is related to the A/D input voltage for the specified input channel according to the following formula: Rx = Vx / (Vrh - Vrl) *256 Where: Rx = The converted value from the A/D result register number x. Vx = The voltage applied to the selected input pin (PE[0:3]). Vrh = The voltage applied to the Vrh (Reference High) pin of the A/D subsystem. Vrl = The voltage applied to the Vrl (Reference Low) pin of the A/D subsystem. What the above equation is trying to say in plain language is that the range (Vrh - Vrl) of the reference volatage is divided into 256 equal increments and is being compared to the unknown input voltage (Vx). Then, using successive approximation techniques, the nearest increment is selected and the result is expressed as number of the increment in the range of 0 - 255 (decimal). For Vx equal to or greater than Vrh, the result will always be 255. For Vx <= Vrl, the result will always be 0. Note - As explained in the Pink Book, Section 12, the HC11 A/D converter subsystem is a successive approximation converter using a "charge-redistribution" (as opposed to the usual R/R2 resitive ladder) technology. The operation of this interesting A/D converter is thoroughly and well explained in the Pink Book, Section 12, "Analog to Digital Converter Subsystem". Further Note - Due to historical precedence, I will continue to refer to Motorola Document M68HC11RM/D, "M68HC11 Reference Manual" as the "Pink Book", even though the latest edition, Rev. 6, 4/2002, has (believe it or not!) _white_ covers!!!!! (Heresy, I shout, heresy!!) Caution - there are substantial differences in page numbers and section numbering between recent editions. All references in this post are with respect Rev. 6. Does i need to combine each register (ADR1 + ADR2+ ADR3 +ADR4 = 8 bit binary data) and keep as 8 bit binary data . Another misconception. No, each result register returns a full eight bit result, no combining is needed. May i know that what is the meaning of " MC68HC11 Floating Point Package" ? software code or hardware? I am not personally familiar with this package, but will observe that there is no such thing as floating point hardware for the MC68HC11 family devices. As for floating point software, I have never needed it for the 'HC11. Any "real number" calculations that I have needed have been handled in C (ICC11 See http://www.imagecraft.com ). Given the somewhat limited computational power of the 'HC11 I avoid floating point calculations at all costs. If the measured analog data is 3.58 V(V max = 5V) , isnt the 6811 A2D will automaticlly convert it as a floating point binary output or just a decimal output only ? A further misconception -- The A/D subsystem only outputs fixed point binary numbers in the range of 0 to 255 (decimal), see the Pink Book Section 12 for further information. Since the RS232 just accept Ascii code, This is also a misconception, RS-232 serial links can handle any arbitrary data format, it is entirely up to the programmer(s) involved to determine the format of the data transmitted. The 'HC11 SC1 can, in fact, transmit as many as 9 bits of data per character so that 8 bit data with parity can be transmitted to any terminal device capable of accepting it. It _is_ true that the 'HC11 SCI doesn't include a parity generator, but this can easily be handled in software if desired. (For critical applications, however, I prefer to provide data integrity using CRC checks as opposed to simple parity checks. so how can i convert the A2D result to ASCII code ( let said 3.58 in ascii code format), See above, there is no need to convert the A/D result to ASCII format. Just transmit the 8 bit result directly to the receiver (much simplier and results is much more efficient use of the serial link). For example, using the formula given above, 3.58 V input should convert to (assuming a 5 V reference): 3.58 / (5.00 - 0.00) * 256 = 183 (decimal) or $B7 (hexidecimal) Just transmit the $B7 via the SCI link. Now, here is an old technique that you may find useful. It is common practice to operate the A/D using Vdd and Vss for Vrh and Vrl respectively (with an appropriate low pass filter (See the Pink Book, Section 2.4.7, "A/D Reference and Port E Pins". Using a nominal 5.000 V supply, this results in an A/D conversion resolution increment of 19.531 millivolts per increment, a rather inconvenient step to work with if you intend to present your conversion results in plain language, decimal format increments. It is also well known that the 'HC11 devices will operate with a supply voltage range of 4.5 to 5.5 (+/-10%) (See the M68HC11 E Series Technical Data, Table A-3). Now, this suggests raising the supply voltage to the 'HC11 slightly to 5.120 V. With 5.120 V applied to (Vrh - Vrl) the increment for an A/D converter step will now be a neat 20.0 millivolts per increment. Thus, conversion to plain language requires a simple shift operation. To restate your example with a 5.12 Volt reference: 3.58 / 5.12 * 256 = 179 (decimal) Now shift left one, 179 * 2 = 358 (Note that 16 bit precision is required, a simple operation on the 'HC11) (Rounding and truncation considerations are left as an excercise to the student) I hope sir can show me the example in asembly code for me. Sorry, I am willing to lead you to knowledge, but I won't do your work for you. If you require further design and conslulting services, feel free to contact me for rates and availability. Best wishes on your project. Thank you > ----- Original Message ----- > From: Gordon Couger > To: > Sent: Thursday, December 26, 2002 3:09 PM > Subject: Re: [m68HC11] Re: A2D binary to Ascii conversion to terminal > Why convert it to flotating point in the first place. Read the A/D register > as a short, int or long as approiate and and send it as is. If you are > going to use it on an Intel or other machine you will have to reverse the > byte in the case of an int and I don't rember how to handle a long. > > If you don't need floating point don't link it in. It is SLOOOOOOW. I woked > whith a 68HC11 for 7 years professionaly and never had to use floating > point. I had to use some awkward fractions and such but I never could afford > the speed loss that F.P. cost. > > I printed them out in hex on a termial because they were 8 bit A/C converers > and hex kept them in orderly rows. I used somting like witten from memory > the sentax may not be correct but you should get the idea.. > > char *hexstr ="0123456789ABCDEF" > void print-hex(char a) > { > char [3] s; > s[2] =0; > s[0]=hex-str[ a%16]; /* mod 16 I may have the operater wrong and the order > reversed */ > s[1]=hex-str[a/16]; > puts(s); > } > > It's crude but small and fast and the string s was often a pointer to a > global string that I have for an output line insted of a local variable. > Again not clean but fast and small. > > Gordon > > Gordon Couger > Stillwater, OK > www.couger.com/gcouger > ----- Original Message ----- > From: <> > To: <> > Sent: Wednesday, December 25, 2002 9:55 AM > Subject: [m68HC11] Re: A2D binary to Ascii conversion to terminal > > --- In , BobGardner@a... wrote: > > > In a message dated 12/25/02 12:31:21 PM Eastern Standard Time, > > > liewbw@m... writes: > > > > > > > >unsigned char addat; > > > > >float volts; > > > > > > > > > >addat=readadchan(); //read a/d > > > > >volts=addat*5.0/255.0; //convert to floating point > > > > >printf("%7.3f\n"); //print out sci terminal > > > > > > > > > > Life's too short to remember which variable is in which register. > > If you > > > really have to see what the assembly looks like, dl the imagecraft > > compiler, > > > compile it, then look at the compiler generated assembly > > language..... I > > > can't imagine anything needing assembler anymore... that's right > > you guys... > > > a challenge... bring it on... send the spec and your tightest > > assembly > > > code... > > > > > > > > > [Non-text portions of this message have been removed] > > > > > > > > > > Herer is my project run > > > > Sensor --> MC68HC11 (A2D) ---> RS232 ---> Computer > > Below is the part of the asembly code for link the measured out to > > port E : > > > > *===================================================================== > > * Init A2D: Initialize the Analog to Digital convertor > > *===================================================================== > > INIT_A2D: > > LDX #$1000 ; needed for the BRCLR command > > LDAA #%10010000 ; Power up A/D with clock delay > > STAA $39,x > > RTS > > > > > > *===================================================================== > > * Read A2D values: > > *===================================================================== > > Read_A2D: > > LDAA #%00000000 ; single scan, multi-mode, pins e0-3 > > STAA $30,x ; WRITE staRTS conversion > > > > > > > > CONVERSION_NOT_DONE > > BRCLR $30,x $80 CONVERSION_NOT_DONE > > LDAA $31,x ; GET VALUE FORM PIN PE0 > > PULX > > RTS > > > > > > *===================================================================== > > * WRITE A2D: WRITE the 8 A2D values in Ram to the TERMinal. > > *===================================================================== > > WRITE_A2D: > > LDAA A2D0 > > LDAB #'0 > > BSR WRITE_A2D_BYTE > > LDAA A2D1 > > INCB > > BSR WRITE_A2D_BYTE > > LDAA A2D2 > > INCB > > BSR WRITE_A2D_BYTE > > LDAA A2D3 > > INCB > > BSR WRITE_A2D_BYTE > > LDAA A2D4 > > INCB > > BSR WRITE_A2D_BYTE > > LDAA A2D5 > > INCB > > BSR WRITE_A2D_BYTE > > LDAA A2D6 > > INCB > > BSR WRITE_A2D_BYTE > > LDAA A2D7 > > INCB > > BSR WRITE_A2D_BYTE > > RTS > > > > WRITE_A2D_BYTE: > > psha > > pshb > > BSR WRITE_TERM > > LDAB #': > > BSR WRITE_TERM > > TAB > > lsrb > > lsrb > > lsrb > > lsrb > > LDY #WA2D_TABle ; 4-bits to HEX > > aby > > LDAB $00,y > > BSR WRITE_TERM > > TAB > > andb #$0F > > LDY #WA2D_TABle > > aby > > LDAB $00,y > > JSR WRITE_TERM > > LDAB #$20 ; Space > > JSR WRITE_TERM > > pulb > > pula > > RTS > > WA2D_TABle: > > fcc "0123456789ABCDEF" > > > > > > > > *===================================================================== > > * WRITE 2 TERMinal: > > * Input: ASCII data in the B register. > > * Action: Wait until transmit buffer is empty, then > > * transmit the data in the B register. > > *===================================================================== > > WRITE_TERM: > > BRCLR $2e,x %10000000 WRITE_TERM ; check Transmit-empty > > STAB $2f,x > > RTS > > > > > > > > > > > > > > > > ============================================== > > What i have done is convert the analog measurement data and sent to > > Port PE0 for conversion. The Voltage reference is 5 V for high and 0 > > v for low.So, how to take the converted data from A2D result and > > shift into a 8 bit binary data and then convert to ascii code . The > > ascii code will transmit to SCI port.Thank you > > > > > > > > > > > > > > > > > > To unsubscribe from this group, send an email to: > > > > > > > > > > > > To unsubscribe from this group, send an email to:

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On Thursday 26 December 2002 08:18, Robert Smith wrote: > I have been watching this thread with interest and have become concerned > that the author has been exposed to some serious misunderstandings with > regard to the operation of the 'HC11 A/D Converter Subsystem, 'HC11 data > formats, and the operation of RS-232 serial data systems in general. > Below, I will inject some comments intended to help him with his project. > > Bob Smith I too have been following this thread, and agree your comments were needed. I am a student and have a basic understanding of the 6811 so I could not have provided such good infomation. I want to take the time to thank you Bob Smith for taking the time to explain all that you did. Your comments are always helpful. Of course that goes for everyone else that posts here. Happy Holidays Thanks, Bob Davis

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In a 68HC11 the A/D converter returns a 8 bit variable that can be handled as a char or short it the compiler suoprts it. The value of the variable it its numeric contents times 1/256 time the refferece voltage for the A/D converter. The refferce voltage is usualy 5 volts but can be lowered to 2.5 volts for better resolution. At no time is it floating point unless you convert to floation point. Considering the low resoluton of the A/D converter using 16 bit intergs and fixed point math is a much faster and uses less memory. You scale every thing by a factor of 10 or 100 and divide by the scaling factor at the end. If you need even faster code scale be a power of 2 so you can us shifts insted of divide instrution to get you results. The divide instruction is one of the slowest instructions on the 68hc11. If you are serious about working with microprocessors I suggest you learn C and develop a set of libraies for common needs. Using C for embeded system is different than using it on PCs. The large slow function like scanf() printf() and functins that alocate memory should be used with extreem caution. They are slow, eat memory and in the case of function that alocat memory can cause real problems in system using small amouts of RAM. A copy of Phluger's(sp) Standard C Liberay is great invetment to see what the library functions are doing and some of the best example C code in the world. For the student there are ports of GCC to the 68hc11, Dunfield's C Compiler and Introl's C compiler all for about 100 UDS. There may be some free GCC compilers but getting them running may be worth the $100 dollars. I have extensively used Dunfield's and Introl and can recomend them with out reservation. Dunfieilds is a full commerical copy for $99 while Introls is a non comercial only version. Dunfiled handles longs a little different than most compilers his can be defiend any size you wish but come with a speed penalty. The real up side to Dunfields compiler is the techical support you get it from the guy that wrote ever line of the code and he makes his living progaming embeded systems. It is an abosluty solid compiler. Using C as scafold for assembly language is the fastest way I have found to deveop programs C is fast enough for 95% of what you do and all the compilers I know of allow for assembly instructions to be included in the C compilers. Here is the set up I use. http://www.couger.com/gcouger/newmicros.html The editor is out of date and no longer supported. There might be some nicer solution to the ROM emulator and I would do any new work on a 68HC12 probably using this board http://www.newmicros.com/index2.php?url=http%3A%2F%2Fwww.newmicros.com%2Fcgi -bin%2Fstore%2Forder.cgi%3Fform%3Dprod_detail%26part%3DNMIX-0022-OEM and I would get the FORTH on it to act as a moniter for debuging hardware. There is nothing like having something you know works that you can load in to test for bugs. This chip comes with CAN and the equilivent for pasenger car networks in place of the extra RS232. That is a very inexpensive set up that give very fast edit, compile, link, load, run, crash, compile times on order of 20 seconds for the compile, link load and run. It is fast enough that it enocourges bad practics of not thinking beforeyou try something. Gordon Gordon Couger Stillwater, OK www.couger.com/gcouger ----- Original Message ----- From: "Liew Ban Wui" <> To: <> Cc: <> Sent: Thursday, December 26, 2002 2:29 AM Subject: Re: [m68HC11] Re: A2D binary to Ascii conversion to terminal > Hi , > Thanks for giving me the advice. Since i am still a beginner for MC68HC11,i hope sir can give me some advice for this problem.I am using MC68HC11A0P F92J for the project in expanded mode .As i know , the A2D results will store into ADR1-ADR4 register ($1031 to $1034).Isnt each register just hold 2 bit data ? Does i need to combine each register (ADR1 + ADR2+ ADR3 +ADR4 = 8 bit binary data) and keep as 8 bit binary data . May i know that what is the meaning of " MC68HC11 Floating Point Package" ? software code or hardware? If the measured analog data is 3.58 V(V max = 5V) , isnt the 6811 A2D will automaticlly convert it as a floating point binary output or just a decimal output only ?Since the RS232 just accept Ascii code, so how can i convert the A2D result to ASCII code ( let said 3.58 in ascii code format),I hope sir can show me the example in asembly code for me .Thank you > ----- Original Message ----- > From: Gordon Couger > To: > Sent: Thursday, December 26, 2002 3:09 PM > Subject: Re: [m68HC11] Re: A2D binary to Ascii conversion to terminal > Why convert it to flotating point in the first place. Read the A/D register > as a short, int or long as approiate and and send it as is. If you are > going to use it on an Intel or other machine you will have to reverse the > byte in the case of an int and I don't rember how to handle a long. > > If you don't need floating point don't link it in. It is SLOOOOOOW. I woked > whith a 68HC11 for 7 years professionaly and never had to use floating > point. I had to use some awkward fractions and such but I never could afford > the speed loss that F.P. cost. > > I printed them out in hex on a termial because they were 8 bit A/C converers > and hex kept them in orderly rows. I used somting like witten from memory > the sentax may not be correct but you should get the idea.. > > char *hexstr ="0123456789ABCDEF" > void print-hex(char a) > { > char [3] s; > s[2] =0; > s[0]=hex-str[ a%16]; /* mod 16 I may have the operater wrong and the order > reversed */ > s[1]=hex-str[a/16]; > puts(s); > } > > It's crude but small and fast and the string s was often a pointer to a > global string that I have for an output line insted of a local variable. > Again not clean but fast and small. > > Gordon > > Gordon Couger > Stillwater, OK > www.couger.com/gcouger > ----- Original Message ----- > From: <> > To: <> > Sent: Wednesday, December 25, 2002 9:55 AM > Subject: [m68HC11] Re: A2D binary to Ascii conversion to terminal > > --- In , BobGardner@a... wrote: > > > In a message dated 12/25/02 12:31:21 PM Eastern Standard Time, > > > liewbw@m... writes: > > > > > > > >unsigned char addat; > > > > >float volts; > > > > > > > > > >addat=readadchan(); //read a/d > > > > >volts=addat*5.0/255.0; //convert to floating point > > > > >printf("%7.3f\n"); //print out sci terminal > > > > > > > > > > Life's too short to remember which variable is in which register. > > If you > > > really have to see what the assembly looks like, dl the imagecraft > > compiler, > > > compile it, then look at the compiler generated assembly > > language..... I > > > can't imagine anything needing assembler anymore... that's right > > you guys... > > > a challenge... bring it on... send the spec and your tightest > > assembly > > > code... > > > > > > > > > [Non-text portions of this message have been removed] > > > > > > > > > > Herer is my project run > > > > Sensor --> MC68HC11 (A2D) ---> RS232 ---> Computer > > Below is the part of the asembly code for link the measured out to > > port E : > > > > *===================================================================== > > * Init A2D: Initialize the Analog to Digital convertor > > *===================================================================== > > INIT_A2D: > > LDX #$1000 ; needed for the BRCLR command > > LDAA #%10010000 ; Power up A/D with clock delay > > STAA $39,x > > RTS > > > > > > *===================================================================== > > * Read A2D values: > > *===================================================================== > > Read_A2D: > > LDAA #%00000000 ; single scan, multi-mode, pins e0-3 > > STAA $30,x ; WRITE staRTS conversion > > > > > > > > CONVERSION_NOT_DONE > > BRCLR $30,x $80 CONVERSION_NOT_DONE > > LDAA $31,x ; GET VALUE FORM PIN PE0 > > PULX > > RTS > > > > > > *===================================================================== > > * WRITE A2D: WRITE the 8 A2D values in Ram to the TERMinal. > > *===================================================================== > > WRITE_A2D: > > LDAA A2D0 > > LDAB #'0 > > BSR WRITE_A2D_BYTE > > LDAA A2D1 > > INCB > > BSR WRITE_A2D_BYTE > > LDAA A2D2 > > INCB > > BSR WRITE_A2D_BYTE > > LDAA A2D3 > > INCB > > BSR WRITE_A2D_BYTE > > LDAA A2D4 > > INCB > > BSR WRITE_A2D_BYTE > > LDAA A2D5 > > INCB > > BSR WRITE_A2D_BYTE > > LDAA A2D6 > > INCB > > BSR WRITE_A2D_BYTE > > LDAA A2D7 > > INCB > > BSR WRITE_A2D_BYTE > > RTS > > > > WRITE_A2D_BYTE: > > psha > > pshb > > BSR WRITE_TERM > > LDAB #': > > BSR WRITE_TERM > > TAB > > lsrb > > lsrb > > lsrb > > lsrb > > LDY #WA2D_TABle ; 4-bits to HEX > > aby > > LDAB $00,y > > BSR WRITE_TERM > > TAB > > andb #$0F > > LDY #WA2D_TABle > > aby > > LDAB $00,y > > JSR WRITE_TERM > > LDAB #$20 ; Space > > JSR WRITE_TERM > > pulb > > pula > > RTS > > WA2D_TABle: > > fcc "0123456789ABCDEF" > > > > > > > > *===================================================================== > > * WRITE 2 TERMinal: > > * Input: ASCII data in the B register. > > * Action: Wait until transmit buffer is empty, then > > * transmit the data in the B register. > > *===================================================================== > > WRITE_TERM: > > BRCLR $2e,x %10000000 WRITE_TERM ; check Transmit-empty > > STAB $2f,x > > RTS > > > > > > > > > > > > > > > > ============================================== > > What i have done is convert the analog measurement data and sent to > > Port PE0 for conversion. The Voltage reference is 5 V for high and 0 > > v for low.So, how to take the converted data from A2D result and > > shift into a 8 bit binary data and then convert to ascii code . The > > ascii code will transmit to SCI port.Thank you > > > > > > > > > > > > > > > > > > To unsubscribe from this group, send an email to: > > > > > > > > > > > > To unsubscribe from this group, send an email to:

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