path: root/software/idm/idm.asm

  ;;
  ;;  spreadspace pic utils
  ;;
  ;;
  ;;  Copyright (C) 2011 Christian Pointner <equinox@spreadspace.org>
  ;;                         
  ;;  This file is part of spreadspace pic utils.
  ;;
  ;;  spreadspace pic utils is free software: you can redistribute it and/or modify
  ;;  it under the terms of the GNU General Public License as published by
  ;;  the Free Software Foundation, either version 3 of the License, or
  ;;  any later version.
  ;;
  ;;  spreadspace pic utils is distributed in the hope that it will be useful,
  ;;  but WITHOUT ANY WARRANTY; without even the implied warranty of
  ;;  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  ;;  GNU General Public License for more details.
  ;;
  ;;  You should have received a copy of the GNU General Public License
  ;;  along with spreadspace pic utils. If not, see <http://www.gnu.org/licenses/>.
  ;;
  ;; -------------------------------------
  ;; PREAMBLE

  LIST      p=16F1847
  include   "p16f1847.inc"
  __config  _CONFIG1,  _FOSC_INTOSC & _WDTE_OFF & _PWRTE_OFF & _MCLRE_ON & _CP_OFF & _CPD_OFF & _BOREN_OFF & _CLKOUTEN_OFF & _IESO_OFF & _FCMEN_OFF
  __config  _CONFIG2,  _WRT_OFF & _PLLEN_OFF & _STVREN_OFF & _BORV_LO & _LVP_OFF


  ;; -------------------------------------
  ;; DEFINES
#define       DEBUG      1

  ;; constants
BUF_STARTH    EQU        H'0020'
BUF_STARTL    EQU        H'0000'
BUF_ENDH      EQU        H'0023'
BUF_ENDL      EQU        H'00BF'
#define       FSRW       FSR0
#define       FSRWH      FSR0H
#define       FSRWL      FSR0L
#define       INDFW      INDF0
#define       FSRR       FSR1
#define       FSRRH      FSR1H
#define       FSRRL      FSR1L
#define       INDFR      INDF1
  
  ;; I/O Pins
;; PortA
#define       C1m        PORTA,0
#define       C2p        PORTA,1
#define       AMP_OUT    PORTA,2
#define       ADC_IN     PORTA,3
#define       SPEAKER    PORTA,4
#define       DBG2       PORTA,6
#define       DBG1       PORTA,7
;; PortB
#define       DBG0       PORTB,0
#define       SDI        PORTB,1
#define       SDO        PORTB,2
#define       INT        PORTB,3
#define       SCK        PORTB,4
#define       CS         PORTB,5
#define       FILTER_EN  PORTB,7

  ;; variables
  ;;  all Pages
CMD           EQU        H'0070'
TMP           EQU        H'0071'

CMDS          EQU        H'007E'
FLAGS         EQU        H'007F'

    ;; bits
;; CMDS
#define       CMD_READ   CMDS,0

;; FLAGS
#define       UNDERRUN   FLAGS,0
#define       OVERRUN    FLAGS,1
  
  ;; -------------------------------------
  ;; Macros
inc_fsr     MACRO PTR,PTRH,PTRL
            LOCAL fsr_wraparound,inc_fsr_end
  addfsr    PTR,1
  movf      PTRH,w
  sublw     BUF_ENDH
  btfss     STATUS,C
  goto      fsr_wraparound
  btfss     STATUS,Z
  goto      inc_fsr_end
  movf      PTRL,w
  sublw     BUF_ENDL
  btfsc     STATUS,C
  goto      inc_fsr_end
fsr_wraparound
  movlw     BUF_STARTH
  movwf     PTRH
  movlw     BUF_STARTL
  movwf     PTRL
inc_fsr_end
  ENDM

  ;; -------------------------------------
  ;; Reset Vector
  org	      .0
  movlb     .1
;  movlw     b'01011000'         ;  1 MHz
;  movlw     b'01100000'         ;  2 MHz
;  movlw     b'01101000'         ;  4 MHz
;  movlw     b'01110000'         ;  8 MHz
  movlw     b'01111000'         ; 16 MHz
  movwf     OSCCON
  goto      init

  ;; -------------------------------------
  ;; Interrupts
  org       .4
  movlb     .0
if DEBUG == 1
  bsf       SPEAKER
endif
  btfsc     PIR1,SSP1IF
  goto      int_spi
  btfsc     PIR1,ADIF
  goto      int_adc
  retfie

  ;; void adcInterrupt()
  ;; {
  ;;   static char value = 0;
  ;;   if (!overrun) {
  ;;     *writePtr = ++value;
  ;;     wbuf_next();
  ;;   }
  ;; }
int_adc
  bcf       PIR1,ADIF
  btfsc     OVERRUN
  retfie
  ;; movlb     .1
  ;; movf      ADRESH,w
  movf      TMP,w
  movwf     INDFW
  incf      TMP,f
  call      wbuf_next
  goto      int_fsr_norestore

  ;; void sspInterrupt()
  ;; {
  ;;   if (cmd_read && spiData == 0) {
  ;;     *readPtr = 0;
  ;;     rbuf_next();
  ;;     spiData = underrun ? -1 : *readPtr;
  ;;   } else if (spiData == 'r') {
  ;;     cmd_read = TRUE;
  ;;     spiData = underrun ? -1 : *readPtr;
  ;;   } else {
  ;;     cmd_read = FALSE;
  ;;     printf("%s\n", "I don't like you!");
  ;;   }
  ;; }
int_spi
  bcf       PIR1,SSP1IF
  movlb     .4
  movf      SSP1BUF,w
  movwf     CMD
  btfsc     STATUS,Z
  goto      int_spi_0
  movlw     'r'
  xorwf     CMD,w
  btfsc     STATUS,Z
  goto      int_spi_r
  ;; other commands
  clrf      CMDS
  retfie

int_spi_0
  btfss     CMD_READ
  retfie
  call      rbuf_next
  movf      INDFR,w
  btfss     UNDERRUN
  movwf     SSP1BUF
  goto      int_fsr_norestore

int_spi_r
  movf      INDFR,w
  btfss     UNDERRUN
  movwf     SSP1BUF
  clrf      CMDS
  bsf       CMD_READ
  retfie

int_fsr_norestore
  movlb     .31
  movf      FSR0H,w
  movwf     FSR0H_SHAD
  movf      FSR0L,w
  movwf     FSR0L_SHAD
  movf      FSR1H,w
  movwf     FSR1H_SHAD
  movf      FSR1L,w
  movwf     FSR1L_SHAD
  retfie  

  ;; -------------------------------------
  ;; SUBROUTINES
  ;; void buf_init()
  ;; {
  ;;   writePtr = bufferStart;
  ;;   readPtr = bufferStart;
  ;;   overrun = FALSE;
  ;;   underrun = TRUE;
  ;;   cmd_read = FALSE;
  ;; }
buf_init
  movlw     BUF_STARTH
  movwf     FSRWH
  movwf     FSRRH
  movlw     BUF_STARTL
  movwf     FSRWL
  movwf     FSRRL
  bcf       OVERRUN
  bsf       UNDERRUN

  movf      BSR,w
  clrf      BSR
  bsf       INT
if DEBUG == 1
  bcf       DBG1
  bsf       DBG2
endif
  movwf     BSR
  return

  ;; -------------------
  ;; void wbuf_next()
  ;; {
  ;;   if (!overrun) {
  ;;     writePtr++;
  ;;     writePtr = writePtr > bufferEnd ? bufferStart : writePtr;
  ;;     underrun = FALSE;
  ;;     if(writePtr == readPtr) {
  ;;       overrun = TRUE;
  ;;     }
  ;;   }
  ;; }
wbuf_next
  btfsc     OVERRUN
  return

  inc_fsr   FSRW,FSRWH,FSRWL
  bcf       UNDERRUN
  movf      BSR,w
  clrf      BSR
  bcf       INT
if DEBUG == 1
  bcf       DBG2
endif
  movwf     BSR

  movf      FSRRH,w
  xorwf     FSRWH,w
  btfss     STATUS,Z
  return
  movf      FSRRL,w
  xorwf     FSRWL,w
  btfss     STATUS,Z
  return
  bsf       OVERRUN
if DEBUG == 1
  movf      BSR,w
  clrf      BSR
  bsf       DBG1
  movwf     BSR
endif
  return

  ;; -------------------
  ;; void rbuf_next()
  ;; {
  ;;   if(!underrun) {
  ;;     readPtr++;
  ;;     readPtr = readPtr > bufferEnd ? bufferStart : readPtr;
  ;;     overrun = FALSE;
  ;;     if(readPtr == writePtr) {
  ;;       underrun = TRUE;
  ;;     }
  ;;   }
  ;; }
rbuf_next
  btfsc     UNDERRUN
  return

  inc_fsr   FSRR,FSRRH,FSRRL
  bcf       OVERRUN
if DEBUG == 1
  movf      BSR,w
  clrf      BSR
  bcf       DBG1
  movwf     BSR
endif

  movf      FSRWH,w
  xorwf     FSRRH,w
  btfss     STATUS,Z
  return
  movf      FSRWL,w
  xorwf     FSRRL,w
  btfss     STATUS,Z
  return
  bsf       UNDERRUN
  movf      BSR,w
  clrf      BSR
  bsf       INT
if DEBUG == 1
  bsf       DBG2
endif
  movwf     BSR
  return

  ;; -------------------------------------
  ;; INIT
init
  ;; BANK 6
  movlb     .6
  clrf      CCPR4H
  movlw     .124
  movwf     CCPR4L
  movlw     b'00001011'
  movwf     CCP4CON

  ;; BANK 4
  movlb     .4
  movlw     b'01000000'
  movwf     SSP1STAT
  movlw     b'00010000'
  movwf     SSP1CON3
  movlw     b'00100100'
  movwf     SSP1CON1
if DEBUG == 1
  bsf       DBG0                ; Pull-up for DBG0
endif

  ;; BANK 3
  movlb     .3
  movlw     b'00001111'         ; PORTA0:3 analog, PORTA4:7, digital
  movwf     ANSELA
  clrf      ANSELB              ; PORTB0:7 digital

  ;; BANK 1
  movlb     .1
  movlw     b'00101111'
  movwf     TRISA
  movlw     b'01110011'
  movwf     TRISB
  movlw     b'01010000'         ; Left Justified, FOSC/16, NEG=VSS,POS=VDD
  movwf     ADCON1
  movlw     b'00001101'         ; AN3, ADC On
  movwf     ADCON0
  movlw     b'01001000'         ; ADIE,SSPIE
  movwf     PIE1
  movlw     b'01011111'         ; Enable Pull UPs, disable T0CKI
  movwf     OPTION_REG

  ;; BANK 0
  movlb     .0
  movlw     .124                ; 8 kHz @ 16MHz
  movwf     PR2
  clrf      TMR1H               ; reset TMR1
  clrf      TMR1L
  movlw     b'00100000'         ; Source Fosc/4, Prescaler 1:4, LP-Osc off, Sync, Timer off
  movwf     T1CON
  clrf      T1GCON
  clrf      PIR1                ; reset all used interupt flags
  movlw     b'01000000'         ; PEIE
  movwf     INTCON

  bcf       FILTER_EN
  call      buf_init
  clrf      CMDS
  clrf      TMP

  bsf       INTCON,GIE

  ;; -------------------------------------
  ;; MAINLOOP
main
if DEBUG == 1
  bcf       SPEAKER
  btfss     DBG0
  goto      enable_t1

  btfsc     T1CON,TMR1ON
  bcf       T1CON,TMR1ON
  goto      main

enable_t1
  btfss     T1CON,TMR1ON
  bsf       T1CON,TMR1ON
endif
  btfss     CS
  goto      main

powerdown:
  clrf      CMDS
  ;; sleep
  ;; nop
  goto	    main

  ;; -------------------------------------
  ;; END
  end