From: ian <ian>
Date: Wed, 28 Dec 2005 23:53:48 +0000 (+0000)
Subject: fix initialisation of reversers polarity_cmds_section
X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ijackson/git?a=commitdiff_plain;h=4c4abb5a55b82ad052e07a33a433eb2e5abed102;p=trains.git

fix initialisation of reversers polarity_cmds_section
---

diff --git a/detpic/reverse.asm b/detpic/reverse.asm
index b607b0b..7d4e76d 100644
--- a/detpic/reverse.asm
+++ b/detpic/reverse.asm
@@ -15,7 +15,7 @@ maske				res	1
 
 polarity_cmds equ 0x5f
 polarity_cmds_section udata polarity_cmds
- res maxpics+1
+ res maxpics
 	; Each byte is:
 	;	11RRRRRR	reverse command for slave, waiting to write
 	;	00000001	this is not a reversers board
@@ -188,13 +188,13 @@ polarity_master_init_boardloop
 	dec_f_ifnz t
 	bra	polarity_master_init_boardloop
 
-	tst_f_ifnz polarity_cmds
+	bt_f_if1 polarity_cmds, 0
 	bra	polarity_bad_masternotused
 
 	; OK, but now we have to work our way back and place
 	; the sentinel
 	mov_lw	0x40 ; meaning `sentinel'
-	tst_f_ifnz INDF0
+	bt_f_if0 INDF0, 0
 	bra	polarity_bad_lastpicused
 polarity_master_init_truncateloop
 	mov_wf	POSTDEC0 ; overwrite with sentinel
@@ -205,6 +205,13 @@ polarity_master_init_truncateloop
 	return
 
 polarity_master_init_board_mask_check
+;  W			preserved
+;  FSR0			unchanged
+;  INDF0		maybe set to `reversers board but no command'
+;  TBLPTR*		used and advanced
+;  TABLAT		trashed
+;  STATUS		trashed
+;  everything else	preserved
 	tblrd_postinc_fixup
 	tst_f_ifnz TABLAT
 	clr_f	INDF0 ; meaning `reversers board but no command to send'