MEL PICBASIC Forum - PICs, CONFIGS and Oscillator Settings for Beginners


  • PICs, CONFIGS and Oscillator Settings for Beginners

    It's not always apparent to beginners to decide exactly which config to use; sometimes it's not clear what ASM config goes with what in the PIC datasheet, sometimes you don't know what file in what folder you're supposed to use as reference, sometimes you're not sure what the default value is or where to get it and sometimes you're just too lazy to look it up yourself.

    This thread is to help us simple folk with a list of PICs, oscillator speed and configs until you know what files to use and how to read the datasheet.


    This is what I'm using in my current project:

    PIC 18F4550, 20 MHz external oscillator, USB operation, not using power from USB cord, using Lab-X1

    PBP 2.60C
    MPASM v4.02


    This goes at the top of my PBP program. You can group them all in ASM/ENDASM if you prefer that method:

    @ __CONFIG _CONFIG1L, _PLLDIV_5_1L & _CPUDIV_OSC1_PLL2_1L & _USBDIV_2_1L
    @ __CONFIG _CONFIG1H, _FOSC_HSPLL_HS_1H
    @ __CONFIG _CONFIG2L, _PWRT_OFF_2L & _BOR_ON_2L & _BORV_43_2L & _VREGEN_ON_2L
    @ __CONFIG _CONFIG2H, _WDT_OFF_2H
    @ __CONFIG _CONFIG3H, _CCP2MX_ON_3H & _PBADEN_OFF_3H & _LPT1OSC_OFF_3H & _MCLRE_ON_3H
    @ __CONFIG _CONFIG4L, _STVREN_ON_4L & _LVP_OFF_4L & _ICPRT_OFF_4L & _XINST_OFF_4L
    DEFINE OSC 48

    Comment out the default configs in 18F4550.INC in PBP folder with a semi-colon like this:

    NOLIST
    ifdef PM_USED
    LIST
    "Error: PM does not support this device. Use MPASM."
    NOLIST
    else
    LIST
    LIST p = 18F4550, r = dec, w = -311, w = -230, f = inhx32
    INCLUDE "P18F4550.INC" ; MPASM Header
    ; __CONFIG _CONFIG1L, _PLLDIV_5_1L & _CPUDIV_OSC1_PLL2_1L & _USBDIV_2_1L
    ; __CONFIG _CONFIG1H, _FOSC_HSPLL_HS_1H & _FCMEN_OFF_1H & _IESO_OFF_1H
    ; __CONFIG _CONFIG2L, _PWRT_OFF_2L & _BOR_ON_2L & _BORV_3_2L & _VREGEN_ON_2L
    ; __CONFIG _CONFIG2H, _WDT_ON_2H & _WDTPS_512_2H
    ; __CONFIG _CONFIG3H, _CCP2MX_ON_3H & _PBADEN_OFF_3H & _LPT1OSC_OFF_3H & _MCLRE_ON_3H
    ; __CONFIG _CONFIG4L, _STVREN_ON_4L & _LVP_OFF_4L & _ICPRT_OFF_4L & _XINST_OFF_4L
    NOLIST
    endif
    LIST

    These are the available options at the bottom of P18F4550 in MPASM folder:

    ;----- CONFIG1L Options --------------------------------------------------
    _PLLDIV_1_1L ; No divide (4MHz input)
    _PLLDIV_2_1L ; Divide by 2 (8MHz input)
    _PLLDIV_3_1L ; Divide by 3 (12MHz input)
    _PLLDIV_4_1L ; Divide by 4 (16MHz input)
    _PLLDIV_5_1L ; Divide by 5 (20MHz input)
    _PLLDIV_6_1L ; Divide by 6 (24MHz input)
    _PLLDIV_10_1L ; Divide by 10 (40MHz input)
    _PLLDIV_12_1L ; Divide by 12 (48MHz input)

    _CPUDIV_OSC1_PLL2_1L ; [OSC1/OSC2 Src: /1][96MHz PLL Src: /2]
    _CPUDIV_OSC2_PLL3_1L ; [OSC1/OSC2 Src: /2][96MHz PLL Src: /3]
    _CPUDIV_OSC3_PLL4_1L ; [OSC1/OSC2 Src: /3][96MHz PLL Src: /4]
    _CPUDIV_OSC4_PLL6_1L ; [OSC1/OSC2 Src: /4][96MHz PLL Src: /6]

    _USBDIV_1_1L ; Clock source from OSC1/OSC2
    _USBDIV_2_1L ; Clock source from 96MHz PLL/2

    ;----- CONFIG1H Options --------------------------------------------------
    _FOSC_XT_XT_1H ; XT oscillator, XT used by USB
    _FOSC_XTPLL_XT_1H ; XT oscillator, PLL enabled, XT used by USB
    _FOSC_ECIO_EC_1H ; External clock, port function on RA6, EC used by USB
    _FOSC_EC_EC_1H ; External clock, CLKOUT on RA6, EC used by USB
    _FOSC_ECPLLIO_EC_1H ; External clock, PLL enabled, port function on RA6, EC used by USB
    _FOSC_ECPLL_EC_1H ; External clock, PLL enabled, CLKOUT on RA6, EC used by USB
    _FOSC_INTOSCIO_EC_1H ; Internal oscillator, port function on RA6, EC used by USB
    _FOSC_INTOSC_EC_1H ; Internal oscillator, CLKOUT on RA6, EC used by USB
    _FOSC_INTOSC_XT_1H ; Internal oscillator, XT used by USB
    _FOSC_INTOSC_HS_1H ; Internal oscillator, HS used by USB
    _FOSC_HS_1H ; HS oscillator, HS used by USB
    _FOSC_HSPLL_HS_1H ; HS oscillator, PLL enabled, HS used by USB

    _FCMEM_OFF_1H ; Disabled
    _FCMEM_ON_1H ; Enabled

    _IESO_OFF_1H ; Disabled
    _IESO_ON_1H ; Enabled

    ;----- CONFIG2L Options --------------------------------------------------
    _PWRT_ON_2L ; Enabled
    _PWRT_OFF_2L ; Disabled

    _BOR_OFF_2L ; Disabled
    _BOR_SOFT_2L ; Controled by SBOREN
    _BOR_ON_ACTIVE_2L ; Enabled when the device is not in SLEEP, SBOREN bit is disabled
    _BOR_ON_2L ; Enabled, SBOREN bit is disabled

    _BORV_46_2L ; 4.6V
    _BORV_43_2L ; 4.3V
    _BORV_28_2L ; 2.8V
    _BORV_21_2L ; 2.1V

    _VREGEN_OFF_2L ; Disabled
    _VREGEN_ON_2L ; Enabled

    ;----- CONFIG2H Options --------------------------------------------------
    _WDT_OFF_2H ; HW Disabled - SW Controlled
    _WDT_ON_2H ; HW Enabled - SW Disabled

    _WDTPS_1_2H ; 1:1
    _WDTPS_2_2H ; 1:2
    _WDTPS_4_2H ; 1:4
    _WDTPS_8_2H ; 1:8
    _WDTPS_16_2H ; 1:16
    _WDTPS_32_2H ; 1:32
    _WDTPS_64_2H ; 1:64
    _WDTPS_128_2H ; 1:128
    _WDTPS_256_2H ; 1:256
    _WDTPS_512_2H ; 1:512
    _WDTPS_1024_2H ; 1:1024
    _WDTPS_2048_2H ; 1:2048
    _WDTPS_4096_2H ; 1:4096
    _WDTPS_8192_2H ; 1:8192
    _WDTPS_16384_2H ; 1:16384
    _WDTPS_32768_2H ; 1:32768

    ;----- CONFIG3H Options --------------------------------------------------
    _MCLRE_OFF_3H ; Disabled
    _MCLRE_ON_3H ; Enabled

    _LPT1OSC_OFF_3H ; Timer1 oscillator configured for high power
    _LPT1OSC_ON_3H ; Timer1 oscillator configured for low power

    _PBADEN_OFF_3H ; PortB<4:0> pins are configured as digital I/O on RESET
    _PBADEN_ON_3H ; PortB<4:0> pins are configured as analog input on RESET

    _CCP2MX_OFF_3H ; CCP2 input/output is multiplexed with RB3
    _CCP2MX_ON_3H ; CCP2 input/output is multiplexed with RC1

    ;----- CONFIG4L Options --------------------------------------------------
    _STVREN_OFF_4L ; Disabled
    _STVREN_ON_4L ; Enabled

    _LVP_OFF_4L ; Disabled
    _LVP_ON_4L ; Enabled

    _ICPRT_OFF_4L ; Disabled
    _ICPRT_ON_4L ; Enabled

    _XINST_OFF_4L ; Disabled
    _XINST_ON_4L ; Enabled

    _DEBUG_ON_4L ; Enabled
    _DEBUG_OFF_4L ; Disabled

    ;----- CONFIG5L Options --------------------------------------------------
    _CP0_ON_5L ; Enabled
    _CP0_OFF_5L ; Disabled

    _CP1_ON_5L ; Enabled
    _CP1_OFF_5L ; Disabled

    _CP2_ON_5L ; Enabled
    _CP2_OFF_5L ; Disabled

    _CP3_ON_5L ; Enabled
    _CP3_OFF_5L ; Disabled

    ;----- CONFIG5H Options --------------------------------------------------
    _CPB_ON_5H ; Enabled
    _CPB_OFF_5H ; Disabled

    _CPD_ON_5H ; Enabled
    _CPD_OFF_5H ; Disabled

    ;----- CONFIG6L Options --------------------------------------------------
    _WRT0_ON_6L ; Enabled
    _WRT0_OFF_6L ; Disabled

    _WRT1_ON_6L ; Enabled
    _WRT1_OFF_6L ; Disabled

    _WRT2_ON_6L ; Enabled
    _WRT2_OFF_6L ; Disabled

    _WRT3_ON_6L ; Enabled
    _WRT3_OFF_6L ; Disabled

    ;----- CONFIG6H Options --------------------------------------------------
    _WRTB_ON_6H ; Enabled
    _WRTB_OFF_6H ; Disabled

    _WRTC_ON_6H ; Enabled
    _WRTC_OFF_6H ; Disabled

    _WRTD_ON_6H ; Enabled
    _WRTD_OFF_6H ; Disabled

    ;----- CONFIG7L Options --------------------------------------------------
    _EBTR0_ON_7L ; Enabled
    _EBTR0_OFF_7L ; Disabled

    _EBTR1_ON_7L ; Enabled
    _EBTR1_OFF_7L ; Disabled

    _EBTR2_ON_7L ; Enabled
    _EBTR2_OFF_7L ; Disabled

    _EBTR3_ON_7L ; Enabled
    _EBTR3_OFF_7L ; Disabled

    ;----- CONFIG7H Options --------------------------------------------------
    _EBTRB_ON_7H ; Enabled
    _EBTRB_OFF_7H ; Disabled

    And this is what they mean further up P18F4550.INC:

    ; 96MHz PLL Prescaler:
    ; PLLDIV = 1 No divide (4MHz input)
    ; PLLDIV = 2 Divide by 2 (8MHz input)
    ; PLLDIV = 3 Divide by 3 (12MHz input)
    ; PLLDIV = 4 Divide by 4 (16MHz input)
    ; PLLDIV = 5 Divide by 5 (20MHz input)
    ; PLLDIV = 6 Divide by 6 (24MHz input)
    ; PLLDIV = 10 Divide by 10 (40MHz input)
    ; PLLDIV = 12 Divide by 12 (48MHz input)
    ;
    ; CPU System Clock Postscaler:
    ; CPUDIV = OSC1_PLL2 [OSC1/OSC2 Src: /1][96MHz PLL Src: /2]
    ; CPUDIV = OSC2_PLL3 [OSC1/OSC2 Src: /2][96MHz PLL Src: /3]
    ; CPUDIV = OSC3_PLL4 [OSC1/OSC2 Src: /3][96MHz PLL Src: /4]
    ; CPUDIV = OSC4_PLL6 [OSC1/OSC2 Src: /4][96MHz PLL Src: /6]
    ;
    ; Full-Speed USB Clock Source Selection:
    ; USBDIV = 1 Clock source from OSC1/OSC2
    ; USBDIV = 2 Clock source from 96MHz PLL/2
    ;
    ; Oscillator Selection bits:
    ; FOSC = XT_XT XT oscillator, XT used by USB
    ; FOSC = XTPLL_XT XT oscillator, PLL enabled, XT used by USB
    ; FOSC = ECIO_EC External clock, port function on RA6, EC used by USB
    ; FOSC = EC_EC External clock, CLKOUT on RA6, EC used by USB
    ; FOSC = ECPLLIO_EC External clock, PLL enabled, port function on RA6, EC used by USB
    ; FOSC = ECPLL_EC External clock, PLL enabled, CLKOUT on RA6, EC used by USB
    ; FOSC = INTOSCIO_EC Internal oscillator, port function on RA6, EC used by USB
    ; FOSC = INTOSC_EC Internal oscillator, CLKOUT on RA6, EC used by USB
    ; FOSC = INTOSC_XT Internal oscillator, XT used by USB
    ; FOSC = INTOSC_HS Internal oscillator, HS used by USB
    ; FOSC = HS HS oscillator, HS used by USB
    ; FOSC = HSPLL_HS HS oscillator, PLL enabled, HS used by USB
    ;
    ; Fail Safe Clock Monitor:
    ; FCMEM = OFF Disabled
    ; FCMEM = ON Enabled
    ;
    ; Internal/External Switch Over:
    ; IESO = OFF Disabled
    ; IESO = ON Enabled
    ;
    ; Power Up Timer:
    ; PWRT = ON Enabled
    ; PWRT = OFF Disabled
    ;
    ; Brown Out Reset:
    ; BOR = OFF Disabled
    ; BOR = SOFT Controled by SBOREN
    ; BOR = ON_ACTIVE Enabled when the device is not in SLEEP, SBOREN bit is disabled
    ; BOR = ON Enabled, SBOREN bit is disabled
    ;
    ; Brown Out Voltage:
    ; BORV = 46 4.6V
    ; BORV = 43 4.3V
    ; BORV = 28 2.8V
    ; BORV = 21 2.1V
    ;
    ; USB Voltage Regulator Enable:
    ; VREGEN = OFF Disabled
    ; VREGEN = ON Enabled
    ;
    ; Watchdog Timer:
    ; WDT = OFF HW Disabled - SW Controlled
    ; WDT = ON HW Enabled - SW Disabled
    ;
    ; Watchdog Postscaler:
    ; WDTPS = 1 1:1
    ; WDTPS = 2 1:2
    ; WDTPS = 4 1:4
    ; WDTPS = 8 1:8
    ; WDTPS = 16 1:16
    ; WDTPS = 32 1:32
    ; WDTPS = 64 1:64
    ; WDTPS = 128 1:128
    ; WDTPS = 256 1:256
    ; WDTPS = 512 1:512
    ; WDTPS = 1024 1:1024
    ; WDTPS = 2048 1:2048
    ; WDTPS = 4096 1:4096
    ; WDTPS = 8192 1:8192
    ; WDTPS = 16384 1:16384
    ; WDTPS = 32768 1:32768
    ;
    ; MCLR Enable:
    ; MCLRE = OFF Disabled
    ; MCLRE = ON Enabled
    ;
    ; Low Power Timer1 Oscillator Enable:
    ; LPT1OSC = OFF Timer1 oscillator configured for high power
    ; LPT1OSC = ON Timer1 oscillator configured for low power
    ;
    ; Port B A/D Enable:
    ; PBADEN = OFF PortB<4:0> pins are configured as digital I/O on RESET
    ; PBADEN = ON PortB<4:0> pins are configured as analog input on RESET
    ;
    ; CCP2 Mux bit:
    ; CCP2MX = OFF CCP2 input/output is multiplexed with RB3
    ; CCP2MX = ON CCP2 input/output is multiplexed with RC1
    ;
    ; Stack Overflow Reset:
    ; STVREN = OFF Disabled
    ; STVREN = ON Enabled
    ;
    ; Low Voltage ICSP:
    ; LVP = OFF Disabled
    ; LVP = ON Enabled
    ;
    ; Dedicated In-Circuit Debug/Programming Enable:
    ; ICPRT = OFF Disabled
    ; ICPRT = ON Enabled
    ;
    ; Extended Instruction Set Enable:
    ; XINST = OFF Disabled
    ; XINST = ON Enabled
    ;
    ; Background Debugger Enable:
    ; DEBUG = ON Enabled
    ; DEBUG = OFF Disabled
    ;
    ; Code Protection Block 0:
    ; CP0 = ON Enabled
    ; CP0 = OFF Disabled
    ;
    ; Code Protection Block 1:
    ; CP1 = ON Enabled
    ; CP1 = OFF Disabled
    ;
    ; Code Protection Block 2:
    ; CP2 = ON Enabled
    ; CP2 = OFF Disabled
    ;
    ; Code Protection Block 3:
    ; CP3 = ON Enabled
    ; CP3 = OFF Disabled
    ;
    ; Boot Block Code Protection:
    ; CPB = ON Enabled
    ; CPB = OFF Disabled
    ;
    ; Data EEPROM Code Protection:
    ; CPD = ON Enabled
    ; CPD = OFF Disabled
    ;
    ; Write Protection Block 0:
    ; WRT0 = ON Enabled
    ; WRT0 = OFF Disabled
    ;
    ; Write Protection Block 1:
    ; WRT1 = ON Enabled
    ; WRT1 = OFF Disabled
    ;
    ; Write Protection Block 2:
    ; WRT2 = ON Enabled
    ; WRT2 = OFF Disabled
    ;
    ; Write Protection Block 3:
    ; WRT3 = ON Enabled
    ; WRT3 = OFF Disabled
    ;
    ; Boot Block Write Protection:
    ; WRTB = ON Enabled
    ; WRTB = OFF Disabled
    ;
    ; Configuration Register Write Protection:
    ; WRTC = ON Enabled
    ; WRTC = OFF Disabled
    ;
    ; Data EEPROM Write Protection:
    ; WRTD = ON Enabled
    ; WRTD = OFF Disabled
    ;
    ; Table Read Protection Block 0:
    ; EBTR0 = ON Enabled
    ; EBTR0 = OFF Disabled
    ;
    ; Table Read Protection Block 1:
    ; EBTR1 = ON Enabled
    ; EBTR1 = OFF Disabled
    ;
    ; Table Read Protection Block 2:
    ; EBTR2 = ON Enabled
    ; EBTR2 = OFF Disabled
    ;
    ; Table Read Protection Block 3:
    ; EBTR3 = ON Enabled
    ; EBTR3 = OFF Disabled
    ;
    ; Boot Block Table Read Protection:
    ; EBTRB = ON Enabled
    ; EBTRB = OFF Disabled
    I haven't figured yet where the default values are set. You probably have to go through the datasheet for that...

    One thing people don't realize is that comments don't take up any space on a PIC (unless you ENABLE Insert Source File Comments in MicroCode Studio under VIEW / COMPILE AND PROGRAM). Feel free to put as many comments at the top (or bottom) of your program if it helps you remember what config does what.

    I like to list them all so I don't have to go back to the datasheet/file when I want to change something.


    EXAMPLE #2:

    PIC Basic Pro X v3.0.8.4
    MicroCode Studio Plus v5.0.0.5
    MPASM v5.65

    This goes at the top of my PBP program.

    #CONFIG
    CONFIG PLLDIV = 5 ; Divide by 5 (20 MHz oscillator input)
    CONFIG CPUDIV = OSC1_PLL2 ; [Primary Oscillator Src: /1][96 MHz PLL Src: /2]
    CONFIG USBDIV = 2 ; USB clock source comes from the 96 MHz PLL divided by 2
    CONFIG FOSC = HSPLL_HS ; HS oscillator, PLL enabled (HSPLL)
    CONFIG FCMEN = OFF ; Fail-Safe Clock Monitor disabled
    CONFIG IESO = OFF ; Oscillator Switchover mode disabled
    CONFIG PWRT = OFF ; PWRT disabled
    CONFIG BOR = ON ; Brown-out Reset enabled in hardware only (SBOREN is disabled)
    CONFIG BORV = 3 ; Minimum setting
    CONFIG VREGEN = ON ; USB voltage regulator enabled
    CONFIG WDT = ON ; WDT enabled
    CONFIG WDTPS = 512 ; 1:512
    CONFIG CCP2MX = ON ; CCP2 input/output is multiplexed with RC1
    CONFIG PBADEN = OFF ; PORTB<4:0> pins are configured as digital I/O on Reset
    CONFIG LPT1OSC = OFF ; Timer1 configured for higher power operation
    CONFIG MCLRE = ON ; MCLR pin enabled; RE3 input pin disabled
    CONFIG STVREN = ON ; Stack full/underflow will cause Reset
    CONFIG LVP = OFF ; Single-Supply ICSP disabled
    CONFIG ICPRT = OFF ; ICPORT disabled
    CONFIG XINST = OFF ; Instruction set extension and Indexed Addressing mode disabled (Legacy mode)
    CONFIG DEBUG = OFF ; Background debugger disabled, RB6 and RB7 configured as general purpose I/O pins
    CONFIG CP0 = OFF ; Block 0 (000800-001FFFh) is not code-protected
    CONFIG CP1 = OFF ; Block 1 (002000-003FFFh) is not code-protected
    CONFIG CP2 = OFF ; Block 2 (004000-005FFFh) is not code-protected
    CONFIG CP3 = OFF ; Block 3 (006000-007FFFh) is not code-protected
    CONFIG CPB = OFF ; Boot block (000000-0007FFh) is not code-protected
    CONFIG CPD = OFF ; Data EEPROM is not code-protected
    CONFIG WRT0 = OFF ; Block 0 (000800-001FFFh) is not write-protected
    CONFIG WRT1 = OFF ; Block 1 (002000-003FFFh) is not write-protected
    CONFIG WRT2 = OFF ; Block 2 (004000-005FFFh) is not write-protected
    CONFIG WRT3 = OFF ; Block 3 (006000-007FFFh) is not write-protected
    CONFIG WRTC = OFF ; Configuration registers (300000-3000FFh) are not write-protected
    CONFIG WRTB = OFF ; Boot block (000000-0007FFh) is not write-protected
    CONFIG WRTD = OFF ; Data EEPROM is not write-protected
    CONFIG EBTR0 = OFF ; Block 0 (000800-001FFFh) is not protected from table reads executed in other blocks
    CONFIG EBTR1 = OFF ; Block 1 (002000-003FFFh) is not protected from table reads executed in other blocks
    CONFIG EBTR2 = OFF ; Block 2 (004000-005FFFh) is not protected from table reads executed in other blocks
    CONFIG EBTR3 = OFF ; Block 3 (006000-007FFFh) is not protected from table reads executed in other blocks
    CONFIG EBTRB = OFF ; Boot block (000000-0007FFh) is not protected from table reads executed in other blocks
    #ENDCONFIG

    DEFINE OSC 48
    Do NOT modify any other config files.


    Robert



    Note: My first version of PBP came on a diskette and I still consider myself a beginner.
    This article was originally published in forum thread: PICs, CONFIGS and Oscillator Settings for Beginners started by Demon View original post