From 98a4ae7dc02dbfde05af2689a93818911d5f222f Mon Sep 17 00:00:00 2001
From: Christian Pointner <equinox@spreadspace.org>
Date: Fri, 26 Jul 2013 14:53:06 +0000
Subject: add SPI based com for 16F1847

git-svn-id: https://svn.spreadspace.org/pic/trunk@96 a09c6847-51d9-44de-8ef2-e725cf50f3c7
---
 bootloader/com-16f1847-spi.inc | 78 ++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 78 insertions(+)
 create mode 100644 bootloader/com-16f1847-spi.inc

(limited to 'bootloader/com-16f1847-spi.inc')

diff --git a/bootloader/com-16f1847-spi.inc b/bootloader/com-16f1847-spi.inc
new file mode 100644
index 0000000..c8c3f1d
--- /dev/null
+++ b/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
-- 
cgit v1.2.3