Obd2
Hi. I have been having problems with HSERIN. I am talking to a ELM327 IC with a PIC16F876A via the TX / RX pins. when I send data (ATZ for example) to the ELM327 through its RX pin from the PIC and have its TX pin connected to a terminal program everything works. I get the "ELM321 V1.2" message. Now when I connect the ELM327 TX pin to my RX pin on the PIC and try to display it on a 2X16 serial display I get same message as would be expected. But that's it. nothing else will display when I send another command. It seems to be stuck at the HSERIN command. I have a debug led in the loop and it stops blinking. So I know it stops there. Some how the RS232 data coming from the ELM327 is locking up HSERIN. If I toggle power it works for the first message again. no others.
Any ideas what is going on with the HSERIN that I am doing wrong?
Below is my test code.
DEFINE OSC 20
DEFINE HSER_RCSTA 90h
DEFINE HSER_TXSTA 24h '20
DEFINE HSER_BAUD 38400
ADCON0 = %00000000
ADCON1 = %00000110
'TRISA = %00000000
'TRISB = %00000000
TRISC = %10000000
OBD_DATA VAR WORD
TX0 VAR BYTE
TX1 VAR BYTE
RX0 VAR BYTE
RX1 VAR BYTE
RX2 VAR BYTE
RX3 VAR BYTE
RX4 VAR BYTE
RX5 VAR BYTE
RX6 VAR BYTE
RX7 VAR BYTE
RX8 VAR BYTE
RX9 VAR BYTE
RX10 VAR BYTE
RX11 VAR BYTE
RX12 VAR BYTE
RX13 VAR BYTE
RX14 VAR BYTE
RX15 VAR BYTE
'****************************** VARIABLES **************************************
TX0 = 01 '01
TX1 = 12 '0C
'****************************** PROGRAM ****************************************
START:
'HSerout [65,84,90,13,10] 'SEND ATZ (13 = CR) (10 = LF)
'HSerout [HEX2 TX0,HEX2 TX1,13,10] 'GET RPM EITHER OR WORKS
HSerout ["010C",13,10] 'GET RPM
HSerin 100,START,[RX0,RX1,RX2,RX3,RX4,RX5,RX6,RX7,RX8,RX9,RX10,RX11, RX12,RX13,RX14,RX15]
HIGH PORTC.1 'FOR DEBUG
PAUSE 500
LOW PORTC.1
SerOut2 PORTC.3,16468,5,[254,128," RPM "]
SerOut2 PORTC.3,16468,5,[254,192,RX0,RX1,RX2,RX3,RX4,RX5,RX6,RX7,RX8,RX9,RX 10,RX11,RX12,RX13,RX14,RX15]
GoTo START
Thanks for any help.
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