Search found 10 matches

I've checked the ADC configuration registers and all seems ok.
I've also ordered the release for my compiler...
Note that all work well on a PIC16F877A. But there is not enough memory for my complet ...

We have provided zener diode for the final board.
The bridge is for prototype board to se if we can adjust the A/D ref between the analog input on AN0 & AN4.
The input signal is 2.5V +/- 0.4.

I have a resistor bridge :
0V -> 10K -> AIN2 -> 5K -> AIN3 -> 10K -> +5V.
I've tried with 1K, 0.5K and 1K, with the same result.
What is the minimun ref value ?[/img]

That is done yet.
The A/D is working correctly with AN0 & AN4.
The problem is on the refs. When the program pass the command line :
setup_adc_ports(A_ANALOG_RA3_RA2_REF);
the ref AIN2 fall ...

The comment in the PIC18F258 is a little bit confuse :

#define A_ANALOG_RA3_RA2_REF 0x8C // A0 A1 A5 Ref=A2,A3

Now, it'ok for the A/D conversion with no refs. thanks.
But the problem with ...

Excuse me, I've forgotten the compiler version :

CCS PCH C Compiler, Version 3.182, 21972

Filename: C:\Tempo\test2.LST

ROM used: 3834 (12%)
...

Here is the code :

#include <18F258.h>
#device ICD=TRUE
#DEVICE ADC=10
#use delay(clock=20000000)
#fuses NOWDT, HS, PUT, NOPROTECT, BROWNOUT, NOLVP, NOCPD, NOWRT, NODEBUG
#use rs232(baud ...

Ok, I'll do it tomorow. All the hardware is at the office.
Thanks.

I've tried the magic number to test. I have the same results with the constants that are defined in the 18F458.H

Hi,
I configure the A/D converter on my µP (i.e. PIC18F458) with external refs on AIN2 & AIN3 respectively at 2V & 3V.
After a reset, when I test the voltage on each ref pin I get the right ...