From e9b4c8c22ec7ed843d120131e2f68164ed424eb4 Mon Sep 17 00:00:00 2001
From: janko-jj <165717176+janko-jj@users.noreply.github.com>
Date: Tue, 16 Jun 2026 02:51:43 +0200
Subject: [PATCH 1/2] add fast UART Rx FIFO clean

---
 src/uart.asm | 11 +++++++++--
 1 file changed, 9 insertions(+), 2 deletions(-)

diff --git a/src/uart.asm b/src/uart.asm
index 4a0a78b..ece469d 100644
--- a/src/uart.asm
+++ b/src/uart.asm
@@ -48,7 +48,15 @@ SMC_skip_baud_init
 		rla				; Now in Bit 0
 		or %10000000			; Set MSB to req. write to upper 7 bits
 		out (c), a
-		ret
+		; stale data taken out from FIFO at max speed
+.staleFIFOclean
+		ld bc, UART_GetStatus
+		in a, (c)
+		rra
+		ret nc
+		ld bc, UART_RxD
+		in a, (c)
+		jr .staleFIFOclean
 
 .baudTable:
 		DEFW 243,248,256,260,269,278,286,234	; 115K
@@ -106,7 +114,6 @@ write:
 	IFDEF TESTING
 		call debug
 	ENDIF
-
 		ld bc, UART_GetStatus
 .wait
 		in a, (c)

From efb586e2e442e8addc5afdfc77e32d7f0e267485 Mon Sep 17 00:00:00 2001
From: janko-jj <165717176+janko-jj@users.noreply.github.com>
Date: Tue, 16 Jun 2026 03:21:24 +0200
Subject: [PATCH 2/2] Removing WaitRaster, adjusting the ESPTimout constant
 calculation   With the WaitRaster and the big constant the timeout became
 infinity   in practice. Therefore after the constant calculation is corrected
   the WaitRaster is removed. The timeout is set to 60 seconds at 28MHz

---
 src/constants.inc.asm |  4 +++-
 src/esp-timeout.asm   | 24 +++---------------------
 2 files changed, 6 insertions(+), 22 deletions(-)

diff --git a/src/constants.inc.asm b/src/constants.inc.asm
index 8369b9c..5ecf40d 100644
--- a/src/constants.inc.asm
+++ b/src/constants.inc.asm
@@ -22,7 +22,9 @@ CPUSpeed              		equ $07
 VARS                    	EQU $5c4b		; addr of variables area
 NEXT_ONE_r3             	EQU $19b8           	; find next variable
 
-ESPTimeout              	EQU 65535*4;65535 	; Use 10000 for 3.5MHz, but 28NHz needs to be 65535
+ESPTimeoutInSeconds       	EQU 60 ; Seconds, use this one to adjust timeout
+                        	; ESPTimeoutI is an 64-bit const which fits CheckESPTimeout
+ESPTimeoutI              	EQU 65535 + ((22*ESPTimeoutInSeconds/10)<<16) ; formula for 28MHz
 
 BORDCR				EQU 23624
 
diff --git a/src/esp-timeout.asm b/src/esp-timeout.asm
index 6692cc7..a50a8ef 100644
--- a/src/esp-timeout.asm
+++ b/src/esp-timeout.asm
@@ -1,9 +1,9 @@
 InitESPTimeout:
 	MODULE InitESPTimeout
 		push hl
-		ld hl, ESPTimeout mod 65536 	; Timeout is a 32-bit value, so save the two LSBs first,
+		ld hl, ESPTimeoutI mod 65536 	; Timeout is a 32-bit value, so save the two LSBs first,
 		ld (CheckESPTimeout.Value), hl
-		ld hl, ESPTimeout / 65536	; then the two MSBs.
+		ld hl, ESPTimeoutI / 65536	; then the two MSBs.
 		ld (CheckESPTimeout.Value2), hl
 		pop hl
 		ret
@@ -18,7 +18,6 @@ Value 	EQU $+1
 		ld hl, SMC
 		dec hl
 		ld (Value), hl
-		call WaitRaster
 		ld a, h
 		or l
 		jr z, Rollover
@@ -36,26 +35,9 @@ Value2 	EQU $+1
 		or l
 		jr z, Failure			; If we hit here, 32 bit value is $00000000
 		dec hl
-		call WaitRaster
 		ld (Value2), hl
-		ld hl, ESPTimeout mod 65536
+		ld hl, ESPTimeoutI mod 65536
 		ld (Value), hl
 		jr Success
 
-// https://github.com/remy/next-http/issues/7
-WaitRaster:
-		push bc
-		push af
-.waitloop:
-		ld bc, $243b
-		ld a, $1f     			; only really care about lsb
-		out (c), a
-		inc b
-		in a, (c)
-		cp 192
-		jr nz, .waitloop
-		pop af
-		pop bc
-		ret
-
 	ENDMODULE