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Hi, I am having diffuculty locating sample codes on how to display results on LEDs using the MC68hc11. I only want the LED to flash on for 1 and nothing on 0. using 3 pins in portb each one will send 1 or 0 to the equivalent LED. I would really appreciate it, if you can provide me or direct me to a code that performs this. Thank you mthem2003 |
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LED display
Started by ●February 18, 2003
Reply by ●February 18, 20032003-02-18
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Hi, no need for the "blink" in the project, but Thank you so much for your reply ( and for the portb message reply as well), i found them to be really helpful. :) mthem2003 --- In , "Nick Reitter, 3rd" <nick@r...> wrote: > Hi, Here is how to control a LED in its simplifiest terms. > First the hardware. Port B requires an inverter (Does not have to be an > inverter. Inverters are nicer. ie. A 1 turns the LED on.) driver to control > a LED. The LED is in series with a 330 ohm current limiting resistor and is > connected between the +5volts and the driver output. The input of the driver > goes to Port B. Use a 7416 or 7404to the driver output. The input of the > driver goes to Port B. All of this is because port B cannot "furnish" the > current required to control a LED. The current is about 16 millamps for a > LED. > The code for turning a bit on is: > ldaa #data > staa $1004 > If the LED is on bit 0, data = $01 > If the LED is on bit 1, data = $02 > If the LED is on bit 2, data =$04 > If the LED is on bit 3, data = $08 > If the LED is on bit 4, data = $10 > If the LED is on bit 5, data = $20 > If the LED is on bit 6, data = $40 > If the LED is on bit 7, data =$80 > You can of course add the data to control multiple bits. > To turn all the bits off use: > clr $1004 > The best way to do turn a bit on without affecting any other bits is using > bit manipulation instructions: > ldx #$1000 > bset $04,x data > Likewise to turn a bit off without affecting any other bits is using bit > manipulation instructions: > ldx #$1000 > bclr $04,x data > > There are other ways to control LEDs connected to Port B, but this will get > the job done. > > Do you also want to know how to make a LED "blink"? > > Nick > > -----Original Message----- > From: mthem2003 <mthem2003@y...> [mailto:mthem2003@y...] > Sent: Tuesday, February 18, 2003 12:36 PM > To: > Subject: [m68HC11] LED display > > Hi, > I am having diffuculty locating sample codes on how to display > results on LEDs using the MC68hc11. I only want the LED to flash on > for 1 and nothing on 0. using 3 pins in portb each one will send 1 > or 0 to the equivalent LED. > I would really appreciate it, if you can provide me or direct me to > a code that performs this. > > Thank you > mthem2003 > > To unsubscribe from this group, send an email to: > > > ">http://docs.yahoo.com/info/terms/ |
Reply by ●February 18, 20032003-02-18
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Hi, Here is how to control a LED in its simplifiest terms. First the hardware. Port B requires an inverter (Does not have to be an inverter. Inverters are nicer. ie. A 1 turns the LED on.) driver to control a LED. The LED is in series with a 330 ohm current limiting resistor and is connected between the +5volts and the driver output. The input of the driver goes to Port B. Use a 7416 or 7404to the driver output. The input of the driver goes to Port B. All of this is because port B cannot "furnish" the current required to control a LED. The current is about 16 millamps for a LED. The code for turning a bit on is: ldaa #data staa $1004 If the LED is on bit 0, data = $01 If the LED is on bit 1, data = $02 If the LED is on bit 2, data =$04 If the LED is on bit 3, data = $08 If the LED is on bit 4, data = $10 If the LED is on bit 5, data = $20 If the LED is on bit 6, data = $40 If the LED is on bit 7, data =$80 You can of course add the data to control multiple bits. To turn all the bits off use: clr $1004 The best way to do turn a bit on without affecting any other bits is using bit manipulation instructions: ldx #$1000 bset $04,x data Likewise to turn a bit off without affecting any other bits is using bit manipulation instructions: ldx #$1000 bclr $04,x data There are other ways to control LEDs connected to Port B, but this will get the job done. Do you also want to know how to make a LED "blink"? Nick -----Original Message----- From: mthem2003 <> [mailto:] Sent: Tuesday, February 18, 2003 12:36 PM To: Subject: [m68HC11] LED display Hi, I am having diffuculty locating sample codes on how to display results on LEDs using the MC68hc11. I only want the LED to flash on for 1 and nothing on 0. using 3 pins in portb each one will send 1 or 0 to the equivalent LED. I would really appreciate it, if you can provide me or direct me to a code that performs this. Thank you mthem2003 To unsubscribe from this group, send an email to: ">http://docs.yahoo.com/info/terms/ |
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