PIC16F527 don't do nothing...

[mtripoli]

After banging on this thing for a few hours I'm beginning to think this device is really chewing gum with metal legs. ;) This is kindof' an odd device; its like a "PIC12Fxxx" but with a "PIC16Fxxx" designation, with built-in opamps (which is why I'm using it).

I'm simply trying to blink an LED. The outputs, across the board, seem to be set as inputs. The first question I have is, how does one set the TRISA on 12 bit devices? If I give it a TRISA command I get an error. Data sheet isn't much help; it refers to "TRISA, TRISB, TRISC". Despite that, I don't think that's the problem given that my LED is on PORTC.0...

As you can see in the code, PORTC.0 is an output, and I believe all the appropriate configuration bits are set properly. Comparators are off, A/D is off, OPAMPS are "on", ANSEL is configured. I know the part is running; I can see the clock out on the clock out pin (DIV/4). MCLR works as well. Just no output from anything. Can someone give this an eyeball and tell me what I've over-looked? Never had so much trouble with any device blinking an led...

BTW: I'm using the latest PBPX 3.0.7.4 with a U2 programmer running meProg v.4.51.

Thanks in advance,

Mike T.


'************************************************* ***************
'* Name : LED_000.BAS *
'************************************************* ***************
#CONFIG
__config _FOSC_INTRC_CLKOUT &_WDTE_OFF &_CP_OFF &_MCLRE_ON &_IOSCFS_4MHz &_CPSW_OFF &_BOREN_OFF &_DRTEN_OFF
#ENDCONFIG

DEFINE OSC 4

INCLUDE "modedefs.bas"


;ALIASES
PBTN VAR PORTA.0 ; INPUT - DIGITAL
; NOT USED VAR PORTA.1 ; OUTPUT - SET LOW
ANIN2 VAR PORTA.2 ; INPUT - ANALOG
; NOT USED VAR PORTA.3 ; OUTPUT - SET LOW
ANIN3 VAR PORTA.4 ; INPUT - ANALOG
OLED VAR PORTA.5 ; OUTPUT - DIGITAL

; OP2_MINUS VAR PORTB.4 ; INPUT - OPAMP
; OP2_PLUS VAR PORTB.5 ; OUTPUT - OPAMP
; NOT USED VAR PORTB.6 ; OUTPUT - DIGITAL
; NOT USED VAR PORTB.7 ; OUTPUT - DIGITAL

LED VAR PORTC.0 ; OUTPUT - DIGITAL
; NOT USED VAR PORTC.1 ; OUTPUT - DIGITAL
; OP2_OUT VAR PORTC.2 ; OUTPUT - ANALOG
; OP1_OUT VAR PORTC.3 ; OUTPUT - ANALOG
; NOT USED VAR PORTC.4 ; OUTPUT - DIGITAL
; NOT USED VAR PORTC.5 ; OUTPUT - DIGITAL
; OP1_MINUS VAR PORTC.6 ; INPUT - ANALOG
; OP1_PLUS VAR PORTC.7 ; INPUT - ANALOG


;PORT CONTROL REGISTERS
;PORTA
;TRISA = %00010101 ;HUH??????

TRISB = %00010000

TRISC = %11000000

; ANSEL
; 7 6 5 4 3 2 1 0
;RC.3 RC.2 RC.1 RC.0 RA.4 RA.2 RA.1 RA.0
ANSEL = %11001100

; INTCON CONTROL REGISTERS
INTCON0 = %00000000
INTCON1 = %00000000

; OPTION CONTROL REGISTER
OPTION_REG = %11000000


;ADC CONTROL REGISTERS
ADCON0 = %00000000 ; ADC DISABLED

; COMPARATOR CONTROL REGISTERS
CM1CON0 = %01000000 ; COMPARATORS OFF - BIT 3
CM2CON0 = %01000000
VRCON.7 = 0 ; VOLTAGE REFERENCE OFF

; OPAMP CONTROL REGISTER
OPACON = %00000011 ; OPAMPS ON


BLINK:
HIGH LED
PAUSE 500
LOW LED
PAUSE 500
GOTO BLINK



end

[Demon]

I use this order, might not make a difference but I like structure (old mainframe programer):

Configs
DEFINES
Special registers
TRIS
Ports
Variables

Robert
:)

[mtripoli]

I'm posting a follow-up to this in case it may help someone else. Though I'm really not happy with this device (the clock jitter in INTOSC mode is too severe for my tastes) here's what I've found out. It appears that BANKSEL does not work on this device. Not sure why; I've reported it to the guys at meLabs and I'm sure they'll get to the bottom of it. In the meantime, assembly to the rescue. If you are not aware of it, there are two things I got from this exercise:

1.) A friend had to remind me that going back to the early days of the '54, there wasn't a TRIS register; there was a TRIS command. This device, being part of the 12-bit core series, uses the TRIS command. So, you load "W" with the value you want TRIS to be, and then use the TRIS command to set the I/O. No big deal, as long as you're aware of it. You can see it in the code.

2.) BANKSEL doesn't work (nor does BSR). There is in fact, yet again, a command for this: MOVLB - move literal to BSR.

Once past those two things, things started looking up (the attached code compiles and runs fine). One thing to keep in mind, generally speaking with any of the devices that have alternate functions on a pin (in other words, all PIC's); set these functions prior to setting TRIS, otherwise these functions will trample on TRIS. Or bit select them, however you like to code. I'm spoiled by the PIC16F1xxx series, and if it wasn't for the fact that these "smaller" devices are so cheap, would use them for everything.


'************************************************* ***************
'* Name : LED_003.BAS *
'************************************************* ***************
;#CONFIG
; __config _FOSC_INTRC_CLKOUT &_WDTE_OFF &_CP_OFF &_MCLRE_ON &_IOSCFS_8MHz &_CPSW_OFF &_BOREN_ON &_DRTEN_OFF
;#ENDCONFIG

DEFINE OSC 8


;ALIASES


LED VAR PORTC.0 ; OUTPUT - DIGITAL


;PORT CONTROL REGISTERS

asm
MOVLB b'00000000' ; SELECT BANK 0

MOVLW b'00000000'
MOVWF ADCON0

MOVLW b'00000000'
MOVWF INTCON0

MOVLW b'00000000'
MOVWF INTCON1

MOVLB b'00000001' ; SELECT BANK 1

MOVLW b'00000000'
MOVWF CM1CON0

MOVLW b'00000000'
MOVWF CM2CON0

MOVLW b'00000000'
MOVWF VRCON

MOVLB b'00000010' ; SELECT BANK 2

MOVLW b'00000000'
MOVWF ADCON0

MOVLW b'00000000'
MOVWF INTCON0

MOVLW b'00000000'
MOVWF INTCON1

MOVLB b'00000011' ; SELECT BANK 3

MOVLW b'00000011'
MOVWF OPACON

MOVLW b'11001101'
MOVWF ANSEL

MOVLB b'00000000'

MOVLW b'00010101' ; LOAD W
TRIS 06h ; LOAD TRIS PORTA

MOVLW b'00010000' ; TRIS PORTB
TRIS 07h

MOVLW b'11000000'
TRIS 08h
endasm


low led


MAIN:
HIGH led
pause 250
low led
pause 250
goto main


end