Post by thread:[PIC]: Migrating to PIC16F84

Hi there, I am fairly new to the PIC, however I have now designed 3 successful applications using the PIC12C508A I have now designed a far more complex application which will probably end up in a PIC16C505 - however I am developing it on a PIC16F84 to get it going. I burnt my first version in a PIC16F84 (NOT A version) this morning and NOTHING. I checked all my hardware and retried - still nothing. I then stripped everything out of the application so that it was just an LED flashing at 1Hz. I am running a 4.0 MHz crystal with 22pF caps. I have simply an LED connected to RB7, Pin4 (MCLR) and all unused inputs tied high. Can anybody see what I have done wrong? What have I missed? Regards, Sean LIST P= 16F84 INCLUDE "P16F84.INC" RADIX DEC ORG 0X5 AUX1_L EQU 0XC AUX1_H EQU 0XD AUX2_L EQU 0XE AUX2_H EQU 0XF AUX EQU 0X10 S0 EQU 0X11 __CONFIG _CP_OFF & _PWRTE_OFF & _WDT_OFF & _XT_OSC MOVLW B'1111' MOVWF TRISA MOVLW B'00000000' MOVWF TRISB STARTHERE MOVLW B'00000000' MOVWF PORTB PAGESEL (DELAY500) CALL DELAY500 MOVLW B'10000000' MOVWF PORTB PAGESEL (DELAY500) CALL DELAY500 PAGESEL (STARTHERE) GOTO STARTHERE DELAY500 ; CREATE A DELAY OF 500MS MOVLW 9;* MOVWF AUX2_L DELAYLAB32 MOVLW 169;* MOVWF AUX1_H;* DELAYLAB22 MOVLW 81;* MOVWF AUX1_L;* DELAYLAB12 CLRWDT DECFSZ AUX1_L, F;* PAGESEL (DELAYLAB12) GOTO DELAYLAB12 CLRWDT DECFSZ AUX1_H, F;* PAGESEL (DELAYLAB22) GOTO DELAYLAB22 CLRWDT DECFSZ AUX2_L, F;* PAGESEL (DELAYLAB32) GOTO DELAYLAB32 RETURN END -- http://www.piclist.com hint: To leave the PICList spam_OUTpiclist-unsubscribe-requestTakeThisOuTmitvma.mit.edu

Isn't MCLR an input pin only? Regards, Jim ----- Original Message ----- From: Sean Alcorn - Avion Sydney <.....sdalcornKILLspam@spam@AVION.COM.AU> To: <PICLISTKILLspamMITVMA.MIT.EDU> Sent: Tuesday, January 01, 2002 8:52 PM Subject: [PIC]: Migrating to PIC16F84 - What am I doing wrong? {Quote hidden}> Hi there, > > I am fairly new to the PIC, however I have now designed 3 successful > applications using the PIC12C508A > > I have now designed a far more complex application which will probably end > up in a PIC16C505 - however I am developing it on a PIC16F84 to get it > going. > > I burnt my first version in a PIC16F84 (NOT A version) this morning and > NOTHING. I checked all my hardware and retried - still nothing. I then > stripped everything out of the application so that it was just an LED > flashing at 1Hz. > > I am running a 4.0 MHz crystal with 22pF caps. I have simply an LED > connected to RB7, Pin4 (MCLR) and all unused inputs tied high. > > Can anybody see what I have done wrong? What have I missed? > > Regards, > > Sean > > > LIST P= 16F84 > INCLUDE "P16F84.INC" > RADIX DEC > ORG 0X5 > AUX1_L EQU 0XC > AUX1_H EQU 0XD > AUX2_L EQU 0XE > AUX2_H EQU 0XF > AUX EQU 0X10 > S0 EQU 0X11 > __CONFIG _CP_OFF & _PWRTE_OFF & _WDT_OFF & _XT_OSC > MOVLW B'1111' > MOVWF TRISA > MOVLW B'00000000' > MOVWF TRISB > STARTHERE > MOVLW B'00000000' > MOVWF PORTB > PAGESEL (DELAY500) > CALL DELAY500 > MOVLW B'10000000' > MOVWF PORTB > PAGESEL (DELAY500) > CALL DELAY500 > PAGESEL (STARTHERE) > GOTO STARTHERE > DELAY500 > ; CREATE A DELAY OF 500MS > MOVLW 9;* > MOVWF AUX2_L > DELAYLAB32 > MOVLW 169;* > MOVWF AUX1_H;* > DELAYLAB22 > MOVLW 81;* > MOVWF AUX1_L;* > DELAYLAB12 > CLRWDT > DECFSZ AUX1_L, F;* > PAGESEL (DELAYLAB12) > GOTO DELAYLAB12 > CLRWDT > DECFSZ AUX1_H, F;* > PAGESEL (DELAYLAB22) > GOTO DELAYLAB22 > CLRWDT > DECFSZ AUX2_L, F;* > PAGESEL (DELAYLAB32) > GOTO DELAYLAB32 > RETURN > END > > -- > http://www.piclist.com hint: To leave the PICList > .....piclist-unsubscribe-requestKILLspam.....mitvma.mit.edu > > -- http://www.piclist.com hint: To leave the PICList EraseMEpiclist-unsubscribe-requestspam_OUTTakeThisOuTmitvma.mit.edu

Hi, I think the code should be something like the following. LIST P= 16F84 INCLUDE "P16F84.INC" RADIX DEC AUX1_L EQU 0X0C AUX1_H EQU 0X0D AUX2_L EQU 0X0E AUX2_H EQU 0X0F AUX EQU 0X10 S0 EQU 0X11 __CONFIG _CP_OFF & _PWRTE_OFF & _WDT_OFF &_XT_OSC ORG 0x00 GOTO BEGIN ORG 0X05 BEGIN MOVLW B'1111' MOVWF TRISA MOVLW B'00000000' MOVWF TRISB STARTHERE MOVLW B'00000000' MOVWF PORTB PAGESEL (DELAY500) . . . END Rgds, Thet Naing Kyaw --- Sean Alcorn - Avion Sydney <sdalcornspam_OUTAVION.COM.AU> wrote: {Quote hidden}> Hi there, > > I am fairly new to the PIC, however I have now > designed 3 successful > applications using the PIC12C508A > > I have now designed a far more complex application > which will probably end > up in a PIC16C505 - however I am developing it on a > PIC16F84 to get it > going. > > I burnt my first version in a PIC16F84 (NOT A > version) this morning and > NOTHING. I checked all my hardware and retried - > still nothing. I then > stripped everything out of the application so that > it was just an LED > flashing at 1Hz. > > I am running a 4.0 MHz crystal with 22pF caps. I > have simply an LED > connected to RB7, Pin4 (MCLR) and all unused inputs > tied high. > > Can anybody see what I have done wrong? What have I > missed? > > Regards, > > Sean > > > LIST P= 16F84 > INCLUDE "P16F84.INC" > RADIX DEC > ORG 0X5 > AUX1_L EQU 0XC > AUX1_H EQU 0XD > AUX2_L EQU 0XE > AUX2_H EQU 0XF > AUX EQU 0X10 > S0 EQU 0X11 > __CONFIG _CP_OFF & _PWRTE_OFF & _WDT_OFF & > _XT_OSC > MOVLW B'1111' > MOVWF TRISA > MOVLW B'00000000' > MOVWF TRISB > STARTHERE > MOVLW B'00000000' > MOVWF PORTB > PAGESEL (DELAY500) > CALL DELAY500 > MOVLW B'10000000' > MOVWF PORTB > PAGESEL (DELAY500) > CALL DELAY500 > PAGESEL (STARTHERE) > GOTO STARTHERE > DELAY500 > ; CREATE A DELAY OF 500MS > MOVLW 9;* > MOVWF AUX2_L > DELAYLAB32 > MOVLW 169;* > MOVWF AUX1_H;* > DELAYLAB22 > MOVLW 81;* > MOVWF AUX1_L;* > DELAYLAB12 > CLRWDT > DECFSZ AUX1_L, F;* > PAGESEL (DELAYLAB12) > GOTO DELAYLAB12 > CLRWDT > DECFSZ AUX1_H, F;* > PAGESEL (DELAYLAB22) > GOTO DELAYLAB22 > CLRWDT > DECFSZ AUX2_L, F;* > PAGESEL (DELAYLAB32) > GOTO DELAYLAB32 > RETURN > END > > -- > http://www.piclist.com hint: To leave the PICList > @spam@piclist-unsubscribe-requestKILLspammitvma.mit.edu > > __________________________________________________ Do You Yahoo!? Send your FREE holiday greetings online! http://greetings.yahoo.com -- http://www.piclist.com hint: To leave the PICList KILLspampiclist-unsubscribe-requestKILLspammitvma.mit.edu

Never mind. I read it wrong. Regards, Jim ----- Original Message ----- From: Sean Alcorn - Avion Sydney <RemoveMEsdalcornTakeThisOuTAVION.COM.AU> To: <PICLISTEraseME.....MITVMA.MIT.EDU> Sent: Tuesday, January 01, 2002 9:26 PM Subject: Re: [PIC]: Migrating to PIC16F84 - What am I doing wrong? {Quote hidden}> on 3/7/07 4:04 PM, jim at EraseMEjamespINTERTEX.NET wrote: > > > Isn't MCLR an input pin only? > > Yes it is. > > Sean > > -- > http://www.piclist.com hint: To leave the PICList > RemoveMEpiclist-unsubscribe-requestEraseMEEraseMEmitvma.mit.edu > > -- http://www.piclist.com hint: To leave the PICList RemoveMEpiclist-unsubscribe-requestspam_OUTKILLspammitvma.mit.edu

Sean- Maybe your assembler detects and automagically sorts this out for you, but if not: {Quote hidden}> DELAYLAB12 > CLRWDT > DECFSZ AUX1_L, F;* > PAGESEL (DELAYLAB12) > GOTO DELAYLAB12 > CLRWDT > DECFSZ AUX1_H, F;* > PAGESEL (DELAYLAB22) > GOTO DELAYLAB22 > CLRWDT > DECFSZ AUX2_L, F;* > PAGESEL (DELAYLAB32) > GOTO DELAYLAB32 > RETURN > END The PAGESEL directives are generating instructions, which are skipped on zero rather than your subsequent GOTO instructions. Result--the GOTO is always executed and you never return from the subroutine. Try commenting out the PAGESEL directives to see if this is indeed the problem. Hope that helps, Steve -- http://www.piclist.com hint: PICList Posts must start with ONE topic: [PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads

on 1/1/02 11:59 PM, S Parkis at RemoveMEparkissTakeThisOuTspamEARTHLINK.NET wrote: Hi Steve, Thanks for your reply. > The PAGESEL directives are generating instructions, which are skipped > on zero rather than your subsequent GOTO instructions. Result--the > GOTO is always executed and you never return from the subroutine. Try > commenting out the PAGESEL directives to see if this is indeed the > problem. My silly BASIC to Assembler compiler puts these in. When I build the file with MPLAB, I get a "message" that the PAGESEL is not necessary, and no code was generated. But I will comment them out and try again. On a related note though, I also get another two messages - relating to lines 13 and 15 - (MOVWF TRISA and MOVWF TRISB) - "Register in operand not in bank 0. Ensure that bank bits are correct." - so I now suspect this could be my problem. I do not understand this bank switching stuff. Cheers, Sean -- http://www.piclist.com hint: PICList Posts must start with ONE topic: [PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads

> lines 13 and 15 - (MOVWF TRISA and MOVWF TRISB) - "Register > in operand not in bank 0. Ensure that bank bits are correct." - so I > now suspect this could be my problem. I do not understand this bank > switching stuff Those are just warning messages. You are being advised to check that the correct register is being worked on. You'll find in the include file (trisa equ 0x85 and trisb equ 0x86) that you are, and no specific bank switching is required on the F84. If you migrate to the F628, then you will have to use rp0 and rp1 to access the tris registers -- http://www.piclist.com hint: PICList Posts must start with ONE topic: [PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads

Sean Alcorn - Avion Sydney wrote: {Quote hidden}> > Hi there, > > I am fairly new to the PIC, however I have now designed 3 successful > applications using the PIC12C508A > > I have now designed a far more complex application which will probably end > up in a PIC16C505 - however I am developing it on a PIC16F84 to get it > going. > > I burnt my first version in a PIC16F84 (NOT A version) this morning and > NOTHING. I checked all my hardware and retried - still nothing. I then > stripped everything out of the application so that it was just an LED > flashing at 1Hz. > > I am running a 4.0 MHz crystal with 22pF caps. I have simply an LED > connected to RB7, Pin4 (MCLR) and all unused inputs tied high. > > Can anybody see what I have done wrong? What have I missed? Your code does not have the register setups? Check how you set up the OPTION etc. :o) -Roman -- http://www.piclist.com hint: PICList Posts must start with ONE topic: [PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads

Hi Sean: The banking capability is an issue to allow PICs to have more than 128 registers (while using the same 12 or 14 bit instruction length). As a Standard (and for compatibility), the TRIS registers are located in bank 1 ,while the PORT registers are found in bank 0 (for the f84). The registers maps for the midrange family may be found at DS31006A pages 6-10 and 6-11. There you will be able to make a comparison between the F84 memory map (as fig 6-6, page 6-11) and the more advanced devices (like F628, 876,877). Se same physical address is used to access both the PORT and TRIS registers, the only diference is the bank selection bits RP0 and RP1 found in the STATUS reg. These warnings are indications that you need to use bank switching instructions to ensure you are working with the correct register. Note that even using an instruction like BSF STATUS,RP0 will make the MPASM still believe in bank 0 (while it compiles and generates the correct code ...) By using the BANKSEL macros you will ensure to work always in the correct bank and will take those warnings off too. that's it, I wish it helps... Fabio Pereira -- http://www.piclist.com hint: PICList Posts must start with ONE topic: [PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads

> Those are just warning messages. You are being advised to check > that the correct register is being worked on. You'll find in the include > file (trisa equ 0x85 and trisb equ 0x86) that you are, and no specific > bank switching is required on the F84. If you migrate to the F628, > then you will have to use rp0 and rp1 to access the tris registers > Jinx: I think the F84 really needs the RP0 bit as it has two memory banks ... Fabio Pereira -- http://www.piclist.com hint: PICList Posts must start with ONE topic: [PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads

Sean: Your start address (0x5) is not correct. If you want to use it you should do: ORG 0x0 GOTO START ORG 0x5 START .... > MOVLW B'1111' > MOVWF TRISA > MOVLW B'00000000' > MOVWF TRISB > STARTHERE > MOVLW B'00000000' > MOVWF PORTB > PAGESEL (DELAY500) The PAGESEL is not needed in 1k devices (as F84A)... {Quote hidden}> CALL DELAY500 > MOVLW B'10000000' > MOVWF PORTB > PAGESEL (DELAY500) > CALL DELAY500 > PAGESEL (STARTHERE) > GOTO STARTHERE > DELAY500 > ; CREATE A DELAY OF 500MS > MOVLW 9;* > MOVWF AUX2_L > DELAYLAB32 > MOVLW 169;* > MOVWF AUX1_H;* > DELAYLAB22 > MOVLW 81;* > MOVWF AUX1_L;* > DELAYLAB12 > CLRWDT You do not need to clear the watchdog timer since you disabled it (WDT_OFF directive), it works only to spend one instruction cycle ... (somethin like a NOP would do the same, without affecting the TO and PD flags.) {Quote hidden}> DECFSZ AUX1_L, F;* > PAGESEL (DELAYLAB12) > GOTO DELAYLAB12 > CLRWDT > DECFSZ AUX1_H, F;* > PAGESEL (DELAYLAB22) > GOTO DELAYLAB22 > CLRWDT > DECFSZ AUX2_L, F;* > PAGESEL (DELAYLAB32) > GOTO DELAYLAB32 > RETURN > END > > -- > http://www.piclist.com hint: To leave the PICList > EraseMEpiclist-unsubscribe-requestspamspamBeGonemitvma.mit.edu > > > -- http://www.piclist.com hint: PICList Posts must start with ONE topic: [PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads

> Jinx: > > I think the F84 really needs the RP0 bit as it has two memory banks ... Yes, but you don't need to use it for accessing the tris registers. These lines are clipped from a program I use quite regularly for the F84 (it was written a long time ago in a different environment, and MPLAB still squawks about using trisa) porta equ 05h ;port a address portb equ 06h ; b trisa equ 85h ; a direction trisb equ 86h ; b start equ 00h ;program start vector org start ;define program start vector goto entry entry movlw 10h tris porta ;porta ...i oooo movlw 00h tris portb ;portb oooo oooo movlw 80h option .............. ================= And how the banksel bits must be used in the F628 in a very similar program start equ 0x00 ;program start vector org 0x00 goto entry entry clrf porta movlw 0x07 ;comparators off movwf cmcon clrf status ;bank0 (clear rp0 and rp1) (snip) bsf status,rp0 ;select bank1 bcf status,rp1 movlw 0x00 ;oooo oooo movwf trisa movlw 0x02 ;oooo ooio movwf trisb movlw 0x80 ;portb pull-ups off movwf option_reg bcf status,rp0 ;back to bank0 bcf status,rp1 -- http://www.piclist.com hint: PICList Posts must start with ONE topic: [PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads

{Quote hidden}> > Jinx: > > > > I think the F84 really needs the RP0 bit as it has two memory banks ... > > Yes, but you don't need to use it for accessing the tris registers. > These lines are clipped from a program I use quite regularly for > the F84 (it was written a long time ago in a different environment, > and MPLAB still squawks about using trisa) > > porta equ 05h ;port a address > portb equ 06h ; b > trisa equ 85h ; a direction > trisb equ 86h ; b > > start equ 00h ;program start vector > > org start ;define program start vector > goto entry > > entry movlw 10h > tris porta ;porta ...i oooo > movlw 00h > tris portb ;portb oooo oooo > movlw 80h > option > .............. > I agree, but you are talking about the tris instruction: it's use is not recommended by Microchip (well, only for future compatibility ...) :-D At least, the EECON1 and EECON2 will need the RP0=1 to be accessed (OPTION_REG too, but there is an option instruction too ...) :-D But that's ok I'm just trying to help .. hehe -- http://www.piclist.com hint: PICList Posts must start with ONE topic: [PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads