diff options
Diffstat (limited to 'software/pic.bootloader/com-16f1847-spi.inc')
| -rw-r--r-- | software/pic.bootloader/com-16f1847-spi.inc | 78 |
1 files changed, 78 insertions, 0 deletions
diff --git a/software/pic.bootloader/com-16f1847-spi.inc b/software/pic.bootloader/com-16f1847-spi.inc new file mode 100644 index 0000000..c8c3f1d --- /dev/null +++ b/software/pic.bootloader/com-16f1847-spi.inc @@ -0,0 +1,78 @@ + ;; + ;; spreadspace pic utils + ;; + ;; + ;; Copyright (C) 2011-2013 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/>. + ;; + + ;; --- transmit byte and add it to csum +com_tx_byte + movlb .4 + movwf SSP1BUF + movlb .0 + bcf INTPIN + xorwf csum,f +com_tx_byte_wait1 + btfsc PORTB,5 + goto com_tx_byte_wait1 +com_tx_byte_wait2 + btfss PORTB,5 + goto com_tx_byte_wait2 + movlb .4 + movf SSP1BUF,w + movlb .0 + bsf INTPIN + return + + ;; ---- wait for byte to be received +com_rx_byte + movlb .4 + btfsc SSP1STAT,BF + goto com_rx_got_byte + btfss SSP1CON1,SSPOV + goto com_rx_byte + movf SSP1BUF,w + bcf SSP1CON1,SSPOV + goto com_rx_byte + +com_rx_got_byte + movf SSP1BUF,w + movlb .0 + return + + ;; ----- initialize com (this is called by bootmacro, it's not a subroutine - no return at the end) +com_init + movlb .3 + bcf ANSELB,ANSB1 ; SDI as digital input + bcf ANSELB,ANSB4 ; SCK as digital input + + movlb .1 + movlw b'01110000' ; set internal OSC to 8MHz + movwf OSCCON + bcf TRISB,2 ; RB2(SDO) = out + bcf INTPIN ; interrupt line to master + + movlb .4 + movlw b'01000000' ; SMP=0,CKE=1 + movwf SSP1STAT + movlw b'00100100' ; SSPEN=1,CKP=0,SSPM=0100(SPI Slave with SS) + movwf SSP1CON1 + bcf SSP1CON3,BOEN + + movlb .0 + bsf INTPIN |