From 1f539bac96dd111efa9212f44151c2718a395087 Mon Sep 17 00:00:00 2001
From: ian <ian>
Date: Mon, 26 Dec 2005 23:58:03 +0000
Subject: [PATCH] init polarity master table

---
 detpic/morse.messages |  3 ++-
 detpic/reverse.asm    | 41 ++++++++++++++++++++++++++++++++++++++---
 2 files changed, 40 insertions(+), 4 deletions(-)

diff --git a/detpic/morse.messages b/detpic/morse.messages
index dac7d8f..35882aa 100644
--- a/detpic/morse.messages
+++ b/detpic/morse.messages
@@ -56,7 +56,6 @@ UER
 UCT
 UCI
 UCP
-URM
 
 # Messages for i2clib, S*
 SM	i2clib+panic:st,:sspstat,:sspcon1,:sspcon2 ; m.,i., ctrlr bad state
@@ -81,6 +80,8 @@ DM	detect:buf0			; master has MM bit set in buf0
 # R - Reversers (polarity)
 RS	FSR0L				; POLARITY message too short
 RL	FSR0L				; POLARITY message too long
+RF					; master board has no reversers
+RG					; too many reversers boards
 
 # P - Points
 PB	points:pointmsg			; Firing point when already busy
diff --git a/detpic/reverse.asm b/detpic/reverse.asm
index e2318cd..4416c10 100644
--- a/detpic/reverse.asm
+++ b/detpic/reverse.asm
@@ -18,7 +18,7 @@ polarity_cmds_section udata polarity_cmds
  res maxpics+1
 	; Each byte is:
 	;	11RRRRRR	reverse command for slave, waiting to write
-	;	00000001	this is not a reversers pic
+	;	00000001	this is not a reversers board
 	;	00000000	we have written any relevant command
 	;	01000000	sentinel
 
@@ -175,8 +175,43 @@ board_next_none_more_message
 
 ;----------------------------------------------------------------------
 polarity_master_init
-	panic	morse_URM
-	; need to set up polarity_cmds
+
+	load_tblptr picno2revmasks
+	mov_lfsr polarity_cmds - 1, 0
+	mov_lw	maxpics
+	mov_wf	t
+	mov_lw	0x01 ; meaning `not a reversers board'
+polarity_master_init_boardloop
+	mov_wf	PREINC0
+	rcall	polarity_master_init_board_mask_check
+	rcall	polarity_master_init_board_mask_check
+	dec_f_ifnz t
+	bra	polarity_master_init_boardloop
+
+	tst_f_ifnz polarity_cmds
+	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
+	bra	polarity_bad_lastpicused
+polarity_master_init_truncateloop
+	mov_wf	POSTDEC0 ; overwrite with sentinel
+	tst_f_ifnz INDF0 ; previous one is also `not reversers board' ?
+	bra	polarity_master_init_truncateloop ; yes
+	; no.  hah, we have truncated it.
+
+	return
+
+polarity_master_init_board_mask_check
+	tblrd_postinc_fixup
+	tst_f_ifnz TABLAT
+	clr_f	INDF0 ; meaning `reversers board but no command to send'
+	return
+
+polarity_bad_masternotused panic morse_RF
+polarity_bad_lastpicused panic morse_RG
 
 ;----------------------------------------------------------------------
 polarity_needwrite
-- 
2.30.2