From: ian <ian>
Date: Mon, 14 Feb 2005 02:32:06 +0000 (+0000)
Subject: master test for I2C setup inverted.   also new in-hex debugging stuff; who knows... 
X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ijackson/git?a=commitdiff_plain;h=e5c006c4b6f1af09cf632f75880d9a9ce1dd5e10;p=trains.git

master test for I2C setup inverted.   also new in-hex debugging stuff; who knows if it will work
---

diff --git a/cebpic/i2c-test.asm b/cebpic/i2c-test.asm
index 513265d..86f54c8 100644
--- a/cebpic/i2c-test.asm
+++ b/cebpic/i2c-test.asm
@@ -13,7 +13,8 @@
 ; In subroutines, unless otherwise stated, W and S may have any
 ; value on entry and will be undefined on exit.
 ;
-; labels ending _if_... and _endif_... are used for if ... then [... else ...]
+; labels ending _if[not_... and _endif_... are used for
+;    if ... then [... else ...]
 ; labels ending _loop are for loops
 ; labels ending _isr are at the start of interrupt service routines
 ;			(which must end with retfie)
@@ -98,6 +99,54 @@ debug macro debugvalue
 	endm
 	endif
 
+;----------------------------------------
+; debughf(REGISTER)
+;	reads REGISTER once and writes it to the serial port in hex
+;	for conditions etc. see "debug", above
+;		Before		After
+;	W	any		undefined
+;	S	any		undefined
+ ifdef	SLOW_VERSION
+DEBUGHF_VALUE	equ	0x040	; getting on towards end of access bank
+				; FIXME if all of program used udata that
+				; would be very nice
+
+debughf macro register
+	movff	register, DEBUGHF_VALUE
+	call	debughf_subroutine
+	endm
+
+debughf_subroutine
+	call	debughf_digit
+	swapf	DEBUGHF_VALUE,1,0
+	call	debughf_digit
+	return
+
+;--------------------
+debughf_digit
+;	transmits bottom nybble of DEBUGHF_VALUE in hex
+;	through serial port, as above
+;			Before		After
+;	W		any		undefined
+; DEBUGHF_VALUE		xxxxDDDD	preserved
+
+	movf	DEBUGHF_VALUE,0,0
+	andlw	0x0f
+	sublw	10
+	sublw	0
+	bn	debughf_digit_ifnot_ge10
+	addlw	'a'-'0'
+debughf_digit_ifnot_ge10
+	addlw	'0'+10
+	goto	polling_serial_transmit
+
+ else
+debughf macro register
+	endm
+ endif
+
+
+	
 ;****************************************************************************
 ; PORTMANTEAU CODE
 ; which contains lists of checks and calls to function-specific
@@ -123,6 +172,11 @@ vector_reset
 
 ;----------------------------------------
 main
+	debug	'J'
+	debughf	SSPSTAT
+	debughf	SSPCON1
+	debughf	SSPCON2
+
 	banksel	I2C_CTRL		; ser BSR=i2c BSR (4)
 	btfsc	I2C_CTRL,I2C_CTRL_MASTER,1 ; check =master?, if so
 	goto	master_main		; goto master main routine
@@ -254,6 +308,8 @@ polling_serial_transmit
 ;	serial port hardware must be suitably initialised
 ;	serial port transmit interrupts must be disabled
 ;	will spin until the byte is transmitted
+;		Before		After
+;	W	byte to xmit	preserved
 
 	movwf	TXREG,0		; move contents of W (i.e. debugvalue)
 				;	to TXREG for transmission
@@ -329,7 +385,7 @@ i2c_setup
 	bcf	IPR1,SSPIP,0	; make interrupt low priority
 
 ; are we master or slave ?
-	btfss	I2C_CTRL,I2C_CTRL_MASTER,1	; test whether PIC is master
+	btfsc	I2C_CTRL,I2C_CTRL_MASTER,1	; test whether PIC is master
 	goto	i2c_setup_if_master
 	goto	i2c_setup_if_slave
 
@@ -391,6 +447,12 @@ wait_for_i2c_interrupt_loop
 	goto	wait_for_i2c_interrupt_loop
 
 	bcf	PIR1,SSPIF,0	; clear interrupt bit
+
+	debug	'I'
+	debughf	SSPSTAT
+	debughf	SSPCON1
+	debughf	SSPCON2
+	
 	return
 
 ;***************************************************************************