From: ian <ian>
Date: Sun, 25 Dec 2005 16:56:56 +0000 (+0000)
Subject: transmit management - initial cut
X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ijackson/git?a=commitdiff_plain;h=731948d7c1ab00213d3218c03a87d652ba84064b;p=trains.git

transmit management - initial cut
---

diff --git a/detpic/program.asm b/detpic/program.asm
index d1909be..dbdfb68 100644
--- a/detpic/program.asm
+++ b/detpic/program.asm
@@ -70,17 +70,18 @@ master_init
 	call	common_local_init
 	call	serial_init
 	call	nmra_init
+	call	serialtxfc_init
 	call	mascan_init
 	return
 
 ;----------------------------------------
 master_interrupt_low
 	enter_interrupt_low
-	;call	ticker_intrl
+	call	ticker_intrl
 	call	nmra_serialrx_intrl
-	;call	serialtx_intrl
-	;call	points_local_intrl
-	;call	i2cm_intrl
+	call	serialtx_intrl
+	call	points_local_intrl
+	call	i2cm_intrl
 	panic	morse_IL
 
 ;----------
diff --git a/detpic/serout.asm b/detpic/serout.asm
index 4b3011a..ff06ac3 100644
--- a/detpic/serout.asm
+++ b/detpic/serout.asm
@@ -13,6 +13,7 @@ serial_addbyte
 ;
 	mov_lfsr outbuf, 0
 	mov_ff	outmsg_end, FSR0L
+	bs_f	PIR1, TXIE ; ensure we get interrupted
 ;...
 serial_addbyte_another
 ;  W			byte to xmit to host	trashed
@@ -30,5 +31,78 @@ serial_addbyte_another
 	; too many
 	panic morse_HB
 
+;----------------------------------------------------------------------
+serialtx_intrl
+	bt_f_if1 INTCON, RBIF
+	rcall	portb_read ; check flow control
+
+	; are we ready to transmit ?
+	bt_f_if0 PIR1, TXIF
+	return
+	bt_f_if0 PIR1, TXIE
+	return
+
+	mov_lfsr outbuf, 0
+	mov_fw	outmsg_begin
+	mov_wf	FSR0L
+	xor_wfw	outmsg_end
+	bra_z	tx_bufempty
+
+	mov_fw	INDF0
+	mov_wf	TXREG
+	bra_n	tx_justsent_noacknmra
+	; we've just sent the last byte of some message:
+	; maybe we push an NMRADONE message on the front
+	mov_fw	acknmra
+	bra_nz	tx_acknmra_insert
+tx_justsent_noacknmra
+	inc_f	outmsg_begin
+	bc_f	outmsg_begin, outbuf_szln2
+	goto	led_green
+
+tx_bufempty
+	; maybe we send an NMRADONE
+	mov_fw	acknmra
+	bra_nz	tx_acknmra_send
+	; nothing at all to do:
+	bc_f	PIR1, TXIE
+	goto	led_black
+
+tx_acknmra_insert
+	sub_wff	acknmra ; we're acking these now
+	mov_wf	INDF0 ; write it over the message we just sent
+	goto	led_green
+
+tx_acknmra_send
+	sub_wff	acknmra ; we're acking these now
+	mov_wf	TXREG
+	goto	led_green
+
+;----------------------------------------
+portb_read
+;  W			undefined	value from PORTB
+	mov_fw	PORTB
+	bc_f	INTCON, RBIF
+
+	bt_w_if0  p0_rs232_fcin >> 4
+	bra	tx_fcdisable
+	; tx enable:
+
+	bs_f	PIR1, TXIE
+	bc_f	INTCON, RBIE
+	return
+
+tx_fcdisable
+	bc_f	PIR1, TXIE
+	bs_f	INTCON, RBIE
+	goto	led_red
+
+;----------------------------------------------------------------------
+serialtxfc_init
+	bs_f	INTCON, RBIE
+	bc_f	INTCON2, RBIP
+	rcall	porb_read
+	return
+
 ;======================================================================
  include final.inc