About the RS232 test

[Goodwinchang]

Dear all

I am new comer for CCS but I have so many problems about using CCS 4.0.12.
Original I try to use PIC12F683 using software RS232 to communicate with PC. But it always fail. I give up.
Now I try to think it should be OK using the hardware RS232 for PIC18F452. But it also fail again.
I post my probelm and please someone to teach me what is the matter.

#include <18F452.h>
#device adc=8

#FUSES NOWDT //No Watch Dog Timer
#FUSES WDT128 //Watch Dog Timer uses 1:128 Postscale
#FUSES HS //High speed Osc (> 4mhz)
#FUSES NOPROTECT //Code not protected from reading
#FUSES NOOSCSEN //Oscillator switching is disabled, main oscillator is source
#FUSES BROWNOUT //Reset when brownout detected
#FUSES BORV20 //Brownout reset at 2.0V
#FUSES NOPUT //No Power Up Timer
#FUSES STVREN //Stack full/underflow will cause reset
#FUSES DEBUG //Debug mode for use with ICD
#FUSES LVP //Low Voltage Programming on B3(PIC16) or B5(PIC18)
#FUSES NOWRT //Program memory not write protected
#FUSES NOWRTD //Data EEPROM not write protected
#FUSES NOWRTB //Boot block not write protected
#FUSES NOWRTC //configuration not registers write protected
#FUSES NOCPD //No EE protection
#FUSES NOCPB //No Boot Block code protection
#FUSES NOEBTR //Memory not protected from table reads
#FUSES NOEBTRB //Boot block not protected from table reads

#use delay(clock=10000000)
#use rs232(baud=9600,parity=N,xmit=PIN_C6,rcv=PIN_C7,bits=8,stream=ABC)
// #use i2c(Master,Fast,sda=PIN_C4,scl=PIN_C3)





#include "F:\Download\Working\CCS\11012006\PIC18F452.h"


void main()
{

setup_adc_ports(NO_ANALOGS);
setup_adc(ADC_OFF);
setup_psp(PSP_DISABLED);
setup_wdt(WDT_OFF);
setup_timer_0(RTCC_INTERNAL);
setup_timer_1(T1_DISABLED);
setup_timer_2(T2_DISABLED,0,1);
setup_timer_3(T3_DISABLED|T3_DIV_BY_1);
setup_oscillator(False);
set_tris_C(0xb7) ;
// TODO: USER CODE!!

delay_ms(255) ;
fputs("test\r",ABC) ;
// input=fgetc(rs232) ;
output_drive(PIN_A0) ;
output_high(PIN_A0) ;
while(1)
{output_toggle(PIN_A0) ;
fputs("test\r",ABC) ;
delay_ms(100) ;
//input=fgetc(rs232) ;


}
}

[Ttelmah]

A series of questions apply.
First, are you using low voltage programming?. If you are, you need to have a pull down resistor on the programming pin. If not, get rid of the 'LVP' fuse, and replace it with 'NOLVP'.
Second, you have 'DEBUG' mode selected. Are you running with a debugger?. If not, the this needs to change.
Next, is your clock 10MHz?.
Next, the big one, How is the connection made to the PC?. You need a MAX232, buffer/inverter, or a circuit to provide a similar function.
Then, general ones round the chip. What is connected to MCLR?. Have you got both supply pins connected?. What decoupling is present?.
Then, simplify your diagnostics.
Have a really short 'main' loop, that just sits toggling a pin (effectively your curent code with every RS232 line removed). Check this pin _is_ toggling. If not, then your chip is not running,and the problem is probably one of the connections like MCLR. Once you have this running, check the frequency. Is it about 5Hz (with the delay shown in your code)?. If not, your oscillator figures are wrong somewhere. Only once this is working, try to progress to the RS232 testing.

Best Wishes