Search found 9 matches

by David Halliday
Wed Sep 12, 2007 5:03 pm
Forum: C and ASM Programming
Topic: Why is the A/D port not linear ?
Replies: 1
Views: 3493

Why is the A/D port not linear ?

Hi I've beening testing the response from an A/D input RA0. By putting the results directly onto an LCD display. but it does not seem to be as linear as I expected . Here are the results that I've achieved. Tested using DC bench supply. 1.0V = 192 2.0V = 384 2.5V = 480 3.0V = 527 4.0V = 704 5.0V = 8...
by David Halliday
Fri Feb 09, 2007 2:58 pm
Forum: C and ASM Programming
Topic: problem saving 16 bit numbers to eeprom Memory
Replies: 8
Views: 10901

problem saving 16 bit numbers to eeprom Memory

Hi me again !! Still struggling with eeprom memory :shock: I'm trying to save a recipe of numbers to eeprom memory. 5 time values ie ,1.5Sec's and a powerlevel say 600 watts. The time values, save and recalls as you would expect. But the powerlevel figure only will save a maximum number of 255 befor...
by David Halliday
Mon Jan 08, 2007 11:12 am
Forum: C and ASM Programming
Topic: Writing data to eeprom memory
Replies: 1
Views: 4278

Writing data to eeprom memory

Hi all I've been trying to learn how to save several variables of information to eeprom memory which can be recalled later which will be stored like a selection of recipes. I know the 16F877A has 256 Bytes of eeprom memory but how many byte will each number variable take-up. Also the manual says it ...
by David Halliday
Mon Nov 27, 2006 10:12 am
Forum: C and ASM Programming
Topic: Frustrating Problem with 2 A/D conversion
Replies: 2
Views: 4978

Problem resolved

Hi Ben

Just to let you know Ive added the adjustment to the code and now it works perfectly.

Thankyou Thankyou Dave :D
by David Halliday
Thu Nov 23, 2006 3:35 pm
Forum: C and ASM Programming
Topic: Frustrating Problem with 2 A/D conversion
Replies: 2
Views: 4978

Frustrating Problem with 2 A/D conversion

Hi me again ! :? I've been learning about how to use the a/d ports on a 16F877A . I have enabled the analog ports and have put two power supply (0-5V) on RA0 and RA1 . The result of the A/D conversion has then been placed upon a 2 Line lcd display. But for some reason when you adjust RA0 it also adj...
by David Halliday
Thu Nov 02, 2006 5:25 pm
Forum: C and ASM Programming
Topic: problem with spi port
Replies: 2
Views: 5421

thankyou still appreciated

:lol: Hi ben Thank for the reply. I was trying to program a serial D/A convertor. Although in the end I managed to send data out of the SPI port I still could not get it working properlty. In the end I decided to bit_bang the bits to the device and all worked as expected although the code is alot lo...
by David Halliday
Thu Aug 31, 2006 12:09 pm
Forum: C and ASM Programming
Topic: problem with spi port
Replies: 2
Views: 5421

problem with spi port

Hi all Does someone have a simple piece of code written in C on how to operate the SPI port. I have downloaded the data manual for the PIC16F877A but being a bit simple. I am still confused. Here is what I've done so far #include<system.h> void main() { Trisc= 11000111; \\ setup port c sspstat= 1100...
by David Halliday
Wed Jun 07, 2006 9:21 am
Forum: C and ASM Programming
Topic: Sending 8-bits of serial data for D/A convertor
Replies: 1
Views: 4908

Sending 8-bits of serial data for D/A convertor

Hi Does anyone have any examples on how to send serial data out of a port in C. In the manual it tells you to use SPI mode (SD0)RC5 to send serial data out of a port but I am not sure how you do this in 'C' ? I assumed that you would need a loop routine simliar to what I have done but how do you shi...
by David Halliday
Mon Jan 23, 2006 5:15 pm
Forum: C and ASM Programming
Topic: New programmer simple problem I don't understand in C
Replies: 1
Views: 5682

New programmer simple problem I don't understand in C

:oops: Hi I'm a very new to programming microcontroller and have been trying to set RA4 as an input and as the switch is hit RB1 shall light and after 4 pulses RB2 should light and RB1 stop and after 10 input pulses it should reset. But for some reason it does not do this. Also RB7 AND RB6 remain on...