From: Leo <erbl259-lmu@yahoo.de>
Date: Fri, 30 Mar 2012 07:16:50 +0000 (+0000)
Subject: * avr/sw-uart.asm
X-Git-Tag: 3.1~12
X-Git-Url: http://cloudbase.mooo.com/gitweb/avrcpm.git/commitdiff_plain/6efd62917aa6ec2eac5fc633c21c28c4830c2087

* avr/sw-uart.asm
  - Empty uart receive buffer on break detection

git-svn-id: svn://cu.loc/avr-cpm/avrcpm/trunk@191 57430480-672e-4586-8877-bcf8adbbf3b7
---

diff --git a/avr/init.asm b/avr/init.asm
index e0bb269..914f399 100644
--- a/avr/init.asm
+++ b/avr/init.asm
@@ -1,4 +1,4 @@
-;    Various functions: init, (RAM) disk, mmc, timer
+;    Hardware initialisation, disk, mmc, timer, DRAM test
 ;
 ;    Copyright (C) 2010 Sprite_tm
 ;    Copyright (C) 2010 Leo C.
diff --git a/avr/sw-uart.asm b/avr/sw-uart.asm
index 8c2b33f..df25d09 100644
--- a/avr/sw-uart.asm
+++ b/avr/sw-uart.asm
@@ -174,7 +174,11 @@ srxi_1l:
 srxi_1fe:
 	sts	srx_char_to,_0			; no stop bit --> framing error --> break
 	sts	srx_state,_0
-	sbr	intstat,(1<<i_break)
+	sbr	intstat,(1<<i_break)		;
+	sts	rxcount,_0			;clear rx buffer
+	sts	rxidx_w,_0
+	sts	rxidx_r,_0
+
 	rjmp	srxi_end2
 
 srxi_1be:
@@ -424,9 +428,12 @@ srx_to:
 	rcall	uartputc
 #endif
 	lds	temp,srx_dr		;only 0 if timeout after leading edge of start bit.
-	tst	temp
+	tst	temp			; --> break
 	brne	srxto_store
 	sbr	intstat,(1<<i_break)
+	sts	rxcount,_0		;clear rx buffer
+	sts	rxidx_w,_0
+	sts	rxidx_r,_0
 	rjmp	srxto_ov
 
 srxto_store:
@@ -465,27 +472,34 @@ srxto_ov:					;endif
 ;Fetches a char from the buffer to temp. If none available, waits till one is.
 
 uartgetc:
+	push	zh
+	push	zl
+	push	temp2
+ugetc_w:
 	lds	temp,rxcount		;Number of characters in buffer
 	tst	temp
-	breq	uartgetc		;Wait for char
+	breq	ugetc_w			;Wait for char
 	
-	push	zh
-	push	zl
 	ldi	zl,low(rxfifo)
 	ldi	zh,high(rxfifo)
-	lds	temp,rxidx_r
-	add	zl,temp
-	brcc	PC+2
-	inc	zh
-	inc	temp
-	andi	temp,RXBUFMASK
-	sts	rxidx_r,temp
+	lds	temp2,rxidx_r
+	add	zl,temp2
+	adc	zh,_0
+	inc	temp2
+	andi	temp2,RXBUFMASK
 	cli
 	lds	temp,rxcount
-	dec	temp
+	subi	temp,1
+	brcc	ugetc_fin
+	sei
+	rjmp	ugetc_w
+
+ugetc_fin:
 	sts	rxcount,temp
+	sts	rxidx_r,temp2
 	sei
 	ld	temp,z		;don't forget to get the char
+	pop	temp2
 	pop	zl
 	pop	zh
 	ret
@@ -507,8 +521,7 @@ sputc_l:
 	ldi	zh,high(txfifo)		;
 	lds	temp,txidx_w		;
 	add	zl,temp			;
-	brcc	PC+2			;
-	inc	zh			;
+	adc	zh,_0			;
 	inc	temp			;
 	andi	temp,TXBUFMASK		;
 	sts	txidx_w,temp		;   txidx_w = ++txidx_w % TXBUFSIZE