adding EEPROM

Started by rauseo82 February 22, 2006
I am a student at the University of Alabama in Huntsville.  I am in a 
senior design class where we are trying to add a different EEPROM to 
a BasicX-24 board.  Looking at help you previously gave via the yahoo 
groups forum, we believe we have figured out how to connect the 
EEPROM to the board.  However, I would be very greatful if you could 
look over the attached schematic and let me know if I am correct.

SF1004                       BX24
SO-------->inverter------->MOSI
SCK<-----------------------SCK
+5V<-----------------------Vcc
SI<------------------------MISO
/CS<------ 1k ohm<---------/CS
	There are a few questions.
	1)  We used the SF1004 from Rabbit semiconductors instead of the 
SF1010.

    I believe that the SF1004 has a built in regulator to drop the +5 
Vin to the  +3 V logic that the SF1004 uses.  Do you know if  this is 
true?
	Also it seems as if the SF1004 converts the SO back to +5V.  However 
it will be inverted.  

Do I still need a FET in order to bring the logic back up to +5V?
	2) I saw that you previously used a 1k ohm pull up resistor for the 
chip select.

    Is this still necessary?

    Does this setup bypass the original EEPROM?
	Here are some links that we used in order to form our hypotheses.
	a)  Interfacing with an ATMEL AT45DB321 4 Meg Byte SPI EEPROM
    http://www.phanderson.com/bx24/rabbit.html

b) SF1004 User's Manual  
http://www.rabbitsemiconductor.com/documentation/docs/manuals/SF1000/S
F1000UM.pdf

c)  Interfacing with an SPI EEPROM

    http://www.phanderson.com/bx24/spieeprom.html
	Thanks in advance,

Steven Rauseo

rauseo82@raus...
rauseo@raus...
	
Steve;

     I had to replace my EEPROM about a year ago.  Don't make the mistake I 
made and try to put a 64K part in it's place; the control signals are 
different for the 64K part and it won't work.  I made a connector and ran 
some wires to the circuitboard that the BX-24 was plugged in to and put a 
DIP sized EEPROM there.  Still works perfectly a year later.

     Schematic
    
http://www.geocities.com/flightdata_recorder/FDR_Schematic_External_EEPROM_v1.0.GIF

     Added connector pins to the of the BX-24 Module
     http://www.geocities.com/flightdata_recorder/2005_04_02_EEPROM_001.jpg

     Added connector and wire with a strain-relief
     http://www.geocities.com/flightdata_recorder/2005_04_02_EEPROM_003.jpg

     Wired to DIP socket
     http://www.geocities.com/flightdata_recorder/2005_04_02_EEPROM_004.jpg

     Homepage
     http://www.geocities.com/flightdata_recorder/
	     Good Luck!
     Ken_S.

At 06:01 PM 2/22/2006, you wrote:
>I am a student at the University of Alabama in Huntsville.  I am in a
>senior design class where we are trying to add a different EEPROM to
>a BasicX-24 board.  Looking at help you previously gave via the yahoo
>groups forum, we believe we have figured out how to connect the
>EEPROM to the board.  However, I would be very greatful if you could
>look over the attached schematic and let me know if I am correct.
>
>SF1004                       BX24
>SO-------->inverter------->MOSI
>SCK<-----------------------SCK
>+5V<-----------------------Vcc
>SI<------------------------MISO
>/CS<------ 1k ohm<---------/CS
	
Hi Steven Rauseo!

I just wanted to pipe in and say how refreshing it is to see a student come
to the forum and show that they have done the research, and have legitimate
questions. Too often we see someone pop-in and basically ask for members of
the forum to do their project for them, and ask questions that make it
obvious they haven't downloaded -- let alone read -- the documentation.

Good luck with your studies! You are obviously beeter than average and
should do very well in your career!

Sloan

----- Original Message ----- 
From: "rauseo82" <rauseo82@raus...>
To: <basicx@basi...>
Sent: Wednesday, February 22, 2006 5:01 PM
Subject: [BasicX] adding EEPROM
	> I am a student at the University of Alabama in Huntsville.  I am in a
> senior design class where we are trying to add a
different EEPROM to
> a BasicX-24 board.  Looking at help you previously gave via the yahoo
> groups forum, we believe we have figured out how to connect the
> EEPROM to the board.  However, I would be very greatful if you could
> look over the attached schematic and let me know if I am correct.
	
Steven,
I agree with Sloan - your research is a breath of fresh air...

Double check your serial in & out.  The terms MOSI and MISO are 
anacronyms for 'Master Out Slave In' and 'Master In Slave Out' 
respectively.  The BX24 is set up as the master (SCK & /CS) as it 
should be.  

Thad

--- In basicx@basi..., "rauseo82" <rauseo82@...> wrote:
>
> 
> SF1004                       BX24
> SO-------->inverter------->MOSI
> SCK<-----------------------SCK
> +5V<-----------------------Vcc
> SI<------------------------MISO
> /CS<------ 1k ohm<---------/CS
	
Steve, you may remember me from school.  As an alternative, you could 
try an I2C EEPROM.  There are many example schematics and 'bit baning' 
routines to read and write I2C EEPROMS with the BX online.  I am not 
familar with the SPI devices, or the implementation of the bus.  I do 
know that the I2C alternative will add some overhead.

Tell Dr. Piccirillo hello. ;) and get your self done with school!

Austin Harkins
	Thad Larson wrote:

> Steven,
> I agree with Sloan - your research is a breath of fresh air...
>
> Double check your serial in & out.  The terms MOSI and MISO are
> anacronyms for 'Master Out Slave In' and 'Master In Slave Out'
> respectively.  The BX24 is set up as the master (SCK & /CS) as it
> should be. 
>
> Thad
>
> --- In basicx@basi..., "rauseo82" <rauseo82@...> wrote:
> >
> >
> > SF1004                       BX24
> > SO-------->inverter------->MOSI
> > SCK<-----------------------SCK
> > +5V<-----------------------Vcc
> > SI<------------------------MISO
> > /CS<------ 1k ohm<---------/CS
>
>
>
>
>
>
>
> SPONSORED LINKS
> Microcontrollers 
>
<http://groups.yahoo.com/gads?t=ms&k=Microcontrollers&w1=Microcontrollers&w2=Microprocessor&w3=Intel+microprocessors&w4=Pic+microcontrollers&c=4&s&.sig=mfaAujKZXA2Z_vxre9sGnQ>

> 	Microprocessor 
>
<http://groups.yahoo.com/gads?t=ms&k=Microprocessor&w1=Microcontrollers&w2=Microprocessor&w3=Intel+microprocessors&w4=Pic+microcontrollers&c=4&s&.sig=9jjd2D3GOLIESVQssLmLsA>

> 	Intel microprocessors 
>
<http://groups.yahoo.com/gads?t=ms&k=Intel+microprocessors&w1=Microcontrollers&w2=Microprocessor&w3=Intel+microprocessors&w4=Pic+microcontrollers&c=4&s&.sig=OMnZuqMZX95mgutt4B-tDw>

>
> Pic microcontrollers 
>
<http://groups.yahoo.com/gads?t=ms&k=Pic+microcontrollers&w1=Microcontrollers&w2=Microprocessor&w3=Intel+microprocessors&w4=Pic+microcontrollers&c=4&s&.sig=Malspbd0T4Rq3M4Q0nHrfw>

>
>
>
> 
> >.
>
>
> 
>