18f8722 two serial ports Problems

[surfer0815]

Hi!
I tried it now for a few days, to get serial com working on 18f8722, so now I hope someone here could give me the tricky bit I have to set for a working pic.

If I compile this code, I can see on both serial Ports on PC the 2 different messages on startup, but Interrupt is not working.

I send a charachter from PC to PIC (on both Ports the same) and nothing happens.

Normaly I should get the "fire-1" or "fire-2" Message, if Interrupt occured, but nothing hapens.

My Compiler Version is 4.110

Hope there is someone who had same Problems an got it out?

//#####8722-serial-test.h###########
#include <18F8722.h>
#device adc=8

#FUSES NOWDT //No Watch Dog Timer
#FUSES WDT128 //Watch Dog Timer uses 1:128 Postscale
#FUSES HS //High speed osc with HW enabled 4X PLL
#FUSES NOPROTECT //Code not protected from reading
#FUSES NOIESO //Internal External Switch Over mode disabled
#FUSES NOBROWNOUT //No brownout reset
#FUSES NOPUT //No Power Up Timer
#FUSES NOCPD //No EE protection
#FUSES STVREN //Stack full/underflow will cause reset
#FUSES NODEBUG //No Debug mode for ICD
#FUSES noLVP //Low Voltage Programming on B3(PIC16) or B5(PIC18)
#FUSES NOWRT //Program memory not write protected
#FUSES NOCPB //No Boot Block code protection
#FUSES NOEBTRB //Boot block not protected from table reads
#FUSES NOEBTR //Memory not protected from table reads
#FUSES NOWRTD //Data EEPROM not write protected
#FUSES NOWRTC //configuration not registers write protected
#FUSES NOWRTB //Boot block not write protected
#FUSES noFCMEN //Fail-safe clock monitor enabled
//#FUSES LPT1OSC //Timer1 configured for low-power operation
#FUSES MCLR //Master Clear pin enabled
#FUSES NOXINST //Extended set extension and Indexed Addressing mode disabled (Legacy mode)
#FUSES MCU //Microcontroller Mode

#use delay(clock=10000000)
#use rs232(baud=9600,parity=N,xmit=PIN_C6,rcv=PIN_C7,bits=8,ERRORS,stream=uart1)
#use rs232(baud=9600,parity=N,xmit=PIN_g1,rcv=PIN_g2,bits=8,errors,stream=uart2)

#define led pin_f0

//#######8722-serial-test.c############
#include "8722-serial-test.h"

short int int_=0,int2_=0;

#int_RDA
void RDA_isr()
{
int_=1;
}

#int_RDA2
void RDA2_isr()
{
int2_=1;
}

void main()
{
port_b_pullups(TRUE);
setup_adc_ports(NO_ANALOGS|VSS_VDD);
setup_adc(ADC_OFF|ADC_TAD_MUL_0);
setup_psp(PSP_DISABLED);
setup_spi(FALSE);
setup_spi2(FALSE);
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_timer_4(T4_DISABLED,0,1);
setup_comparator(NC_NC_NC_NC);
setup_vref(FALSE);
//enable_interrupts(INT_RDA);
enable_interrupts(INT_RDA2);
enable_interrupts(GLOBAL);
setup_low_volt_detect(FALSE);
setup_oscillator(False);

output_high(led);delay_ms(500);output_low(led);delay_ms(500);output_high(led);delay_ms(500);output_low(led);

fprintf(uart1,"here i am uart1");
fprintf(uart2,"here i am uart2");

while(1){
If (int_==1){
disable_interrupts(INT_RDA);
output_toggle(led);
fprintf(uart1,"fire-1");
int_=0;
enable_interrupts(INT_RDA);
}
If (int2_==1){
disable_interrupts(INT_RDA2);
output_toggle(led);
fprintf(uart2,"fire-2");
int2_=0;
enable_interrupts(INT_RDA2);
}


}
}

[surfer0815]

Ok, I tried a few things more and here is what i got:

If I put this to one of the ISR Routines: fprintf(uart1,"int occured");
I send a char to the pic, and then I see an endless output off "int occuredint occuredint occured....."

So the Problem seems to be, that the Pic never gets out of the ISR again, but why?

Does CCS not clear the Interrupt Flag bit by itself, so a new interrupt can occur?

[drh]

You need to read the RCREG in the isr to clear the RX interrupt flag.
_________________
David

[jecottrell]

[Ttelmah]

[surfer0815]

David (drh):

Thats it! Thanks a lot!
If i read the rcreg1 in isr1 and rcreg2 in isr2, the code WORKS!!!!

jecottrell:

I tried out your posted code, but same issue as my own code, if i send one char, programm hangs in isr.

But if i clear rcreg1 and rcreg2, your code is working and putting chars out!

For now I just worked with one single serial port, and didn´t had this Problems, could it be a compiler bug?

Thanks for your help guys!

[surfer0815]

Ttelmah:

You are right, that the incoming char, has to be read in the isr itself, otherwise rcreg is not cleared and the isr loops endless times!

Now I put a simple buf=fgetc(ua1); to the isr and rcreg is cleared automatically!

[jecottrell]

Excellent.

That's interesting to know, it's not the ISR that clears the interrupt, its reading the character.

Are there any other Interrupts that are like that, merely calling the ISR doesn't clear the INT bit?

Thanks.

[Ttelmah]