From: ian <ian>
Date: Sat, 19 Jan 2008 16:33:21 +0000 (+0000)
Subject: master waits a bit before starting so that slaves can wake up
X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ijackson/git?a=commitdiff_plain;h=79749789108df66dee6fd4c15a85c70c0f6aab7d;p=trains.git

master waits a bit before starting so that slaves can wake up
---

diff --git a/detpic/program.asm b/detpic/program.asm
index a2b904c..01ebfbb 100644
--- a/detpic/program.asm
+++ b/detpic/program.asm
@@ -60,6 +60,7 @@ master_init
 	call	memory_erase
 	clr_f	flags
 	call	serial_init
+	call	startwait
 	call    i2cm_init
 	call	serialtxbuf_init
 	call    polarity_master_init
@@ -88,6 +89,27 @@ master_interrupt_low @
 	call	i2cm_intrl
 	panic	morse_IL
 
+;----------------------------------------
+startwait
+; We pause before starting up to give slaves a chance to wake up.
+;
+;  Timer 0		any		trashed, left running
+;  GIEH, GIEL		remain continuously disabled
+;
+	clr_f	T0CON
+	bc_f	INTCON,TMR0IF
+	mov_lw	startwait_master_t0inith
+	mov_wf	TMR0H
+	mov_lw	startwait_master_t0initl
+	mov_wf	TMR0L
+	mov_lw	(1<<TMR0ON) | startwait_master_t0scale
+	mov_wf	T0CON
+startwait_loop
+	bt_f_if0 INTCON,TMR0IF
+	bra	startwait_loop
+	;...done.
+	return
+
 ;----------------------------------------------------------------------
 serialrx_table_section	code	0x2000
 
diff --git a/detpic/program.clocks b/detpic/program.clocks
index 8584d2e..ff85d79 100644
--- a/detpic/program.clocks
+++ b/detpic/program.clocks
@@ -1,16 +1,22 @@
 # Each line is:
-#  <name>	M|S|MS		how	interval
+#  <name>	M|S|MS[T]	how	interval
 # where how is one of
-#  T1ov T3ov
+#  T0ov8 T0ov16 T1ov T3ov
 #	set  T[13]CON to  <stuff> | <name>_{master,slave}_t[13]scale
 #	load TMR[13][HL] with  <name>_{master,slave}_t[13]init[hl]
 #       or to put it another way, TMR[13] with
 #		65535 - <name>_{master,slave}_t[13]cycles
 #	then time to overflow will be specified time
+#  T2period
+#	set T2CON to  <stuff> | <name>_{master,slave}_t2scale
+#	set PR2 to  <name>_{master,slave}_t2cycles
+# M and S mean generate <name>_{master,slave}_<things> respectively
+# T means generate <name>_{us,ms}
 
 points		MS	T3ov		10ms
 tick		MST	T2period	1ms
 nmra		M	T0ov8		58us-10cy
+startwait	M	T0ov16		10ms
 
 ; we do morse at 18wpm according to the PARIS standard
 ; (ie a unit time of 66ms) using timer0 (DS p108)