diff options
Diffstat (limited to 'bootloader/com-16f887-spi.inc')
| -rw-r--r-- | bootloader/com-16f887-spi.inc | 64 |
1 files changed, 64 insertions, 0 deletions
diff --git a/bootloader/com-16f887-spi.inc b/bootloader/com-16f887-spi.inc new file mode 100644 index 0000000..7f501cf --- /dev/null +++ b/bootloader/com-16f887-spi.inc @@ -0,0 +1,64 @@ + ;; + ;; 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 + ;; TODO add write + xorwf csum,f + return + + ;; ---- wait for byte to be received +com_rx_byte + bsf STATUS,RP0 + btfsc SSPSTAT,BF + goto com_rx_got_byte + bcf STATUS,RP0 + btfss SSPCON,SSPOV + goto com_rx_byte + movf SSPBUF,w + bcf SSPCON,SSPOV + goto com_rx_byte + +com_rx_got_byte + bsf STATUS,RP0 + movf SSPBUF,w + return + + ;; ----- initialize com (not a subroutine, com_init is called by generic_init +com_init + ;; bank 3 + bsf STATUS,RP0 + bsf STATUS,RP1 + bcf ANSEL,ANS4 ; RA5/SS as digital input + + ;; bank 1 + bcf STATUS,RP1 + movlw b'01110000' ; set internal OSC to 8MHz + movwf OSCCON + movlw b'01000000' ; SMP=0,CKE=1 + movwf SSPSTAT + bcf TRISC,5 ; RC5(SDO) = out + + ;; bank 0 + bcf STATUS,RP0 + movlw b'00100100' ; SSPEN=1,CKP=0,SSPM=0100(SPI Slave with SS) + movwf SSPCON |