kolea
Newbie level 2
Hey folks.
I'm new to PIC programming and my project is to take 4 analog samples (2 voltage; 2 current - LT6101) and 1 digital (temperature - DS18S20) sample.
My initial challenge was to get good communication, but I have resolved that and I get good outputs via RS232 (MAX3232) to hyperterminal (HT).
I am now attempting to sample one port for voltage (through a 90.9k/10k divider) and output that value to HT.
With the code below, I get no output to HT (I have a blink subroutine to execute when I think a sample is being taken). Also, after a few cycles the sample 'heartbeat' stays high and no longer pulses.
This code builds with no errors.
I would appreciate any recommendations (and general critique of my code; I'm very new to this and want to learn the proper setup now).
Thank you in advance for any assistance you can provide.
If there is any more information I need to provide please let me know as well.
I'm new to PIC programming and my project is to take 4 analog samples (2 voltage; 2 current - LT6101) and 1 digital (temperature - DS18S20) sample.
My initial challenge was to get good communication, but I have resolved that and I get good outputs via RS232 (MAX3232) to hyperterminal (HT).
I am now attempting to sample one port for voltage (through a 90.9k/10k divider) and output that value to HT.
With the code below, I get no output to HT (I have a blink subroutine to execute when I think a sample is being taken). Also, after a few cycles the sample 'heartbeat' stays high and no longer pulses.
This code builds with no errors.
I would appreciate any recommendations (and general critique of my code; I'm very new to this and want to learn the proper setup now).
Thank you in advance for any assistance you can provide.
If there is any more information I need to provide please let me know as well.
Code:
list p=16f88
#include <P16F88.inc>
errorlevel -302
__CONFIG _CONFIG1, _CP_OFF & _CCP1_RB0 & _DEBUG_OFF & _WRT_PROTECT_OFF & _CPD_OFF & _LVP_OFF & _BODEN_OFF & _MCLR_OFF & _PWRTE_ON & _WDT_OFF & _INTRC_IO
__CONFIG _CONFIG2, _IESO_OFF & _FCMEN_OFF
; *** User Registers ***
CNT1 equ 0x20
CNT2 equ 0x21
CNT3 equ 0x22
TEMP equ 0x23
TXDATA equ 0x25
RXDATA equ 0x26
HEXNUM equ 0x27
AHN equ 0x28
ALN equ 0x29
CNT4 equ 0x2A
CNT5 equ 0x2B
; *** Bit Definitions ***
#define IRP_bit STATUS,7 ; register bank select (indirect addressing)
#define RP1_bit STATUS,6 ; register bank select (direct addressing)
#define RP0_bit STATUS,5 ; register bank select (direct addressing)
#define LED PORTB,3 ; LED
; *** Reset Vectors ***
ORG 0x000
goto normal_entry
ORG 0x020
normal_entry
goto main
; *** Subroutines ****
; *** Delay for 100 ms @ 4 MHz ***
ms100 movlw D'100'
movwf CNT2
loop_a movlw D'250'
movwf CNT1
loop_b nop
decfsz CNT1,f
goto loop_b
decfsz CNT2,f
goto loop_a
return
; *** Delay for 200 ms @ 4 MHz ***
ms200 call ms100
call ms100
return
; *** Delay for 0.5 s @ 4 MHz ***
halfsec call ms200
call ms200
call ms100
return
; *** Delay for 1 s @ 4 MHz ***
onesec call halfsec
call halfsec
return
; *** Delay for 2 s @ 4 MHz ***
twosec call onesec
call onesec
return
; *** Delay for 5 s @ 4 MHz ***
fivesec call twosec
call twosec
call onesec
return
; *** Delay for 480 us @ 4 MHz ***
us480 movlw D'120'
movwf CNT1
loop4us nop
decfsz CNT1,f
goto loop4us
return
; *** Delay for 60 us @ 4 MHz
us60 movlw D'15'
movwf CNT1
goto loop4us
; *** ADC ***
get_ad movlw D'100'
movwf CNT1
acquire decfsz CNT1,F
goto acquire
bsf ADCON0,GO_DONE
convert btfsc ADCON0,GO_DONE
goto convert
return
; *** Hex to ascii convert, convert byte in HEXNUM ***
n2s clrf AHN
swapf HEXNUM,W
nibble andlw 0x0F
movwf ALN
sublw D'9'
btfss STATUS,C
goto hexa2f
movlw 0x30
goto ascii
hexa2f movlw 0x37
ascii addwf ALN,f
movf AHN,f
btfss STATUS,Z
goto aln_ok
movf ALN,W
movwf AHN
movf HEXNUM,W
goto nibble
aln_ok return ; result in AHN and ALN
; *** Calls n2s and then transmits with ser_tx ***
n2s_tx call n2s
movf AHN,W
movwf TXDATA
call ser_tx
movf ALN,W
movwf TXDATA
call ser_tx
return
; *** Read and transmit voltage ***
voltage call get_ad
movf ADRESH,W
movwf HEXNUM
call n2s_tx
return
; *** Blink ***
blink bsf LED
call twosec
bcf LED
call twosec
return
blink_fast bsf LED
call ms200
bcf LED
call ms200
return
; *** Serial port transmit ***
ser_tx btfss PIR1,TXIF
goto ser_tx
movf TXDATA,w
movwf TXREG
return
; *** Serial Test ***
;serial_test
; movlw 0x21
; movwf TXDATA
; call ser_tx
; movlw 0x0D
; movwf TXDATA
; call ser_tx
; movlw 0x0A
; movwf TXDATA
; call ser_tx
; call twosec
; call ser_tx
;
; return
; *** Main Code ***
main bcf IRP_bit
bcf RP0_bit
bcf RP1_bit
movlw OSCCON
movwf FSR
movlw B'01100000'
iorwf INDF,f
movlw ANSEL
movwf FSR
movlw B'00010000'
movwf INDF
movlw TRISA
movwf FSR
movlw B'01111111'
movwf INDF
movlw TRISB
movwf FSR
movlw B'10110110'
movwf INDF
movlw ADCON0
movwf FSR
movlw B'01000001'
movwf INDF
movlw ADCON1
movwf FSR
movlw B'01000000'
movwf INDF
movlw TRISB
movwf FSR
movlw B'00100100'
iorwf INDF,f
movlw TXSTA
movwf FSR
movlw B'00100100'
movwf INDF
movlw B'10010000'
movwf RCSTA
movlw SPBRG
movwf FSR
movlw D'12'
movwf INDF
clrf RXDATA
bcf LED
call onesec
call blink
loop call voltage
call fivesec
goto loop
END
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