From ebf7dfabfadaa9d9fdb4ba412cfea7a5e4031787 Mon Sep 17 00:00:00 2001
From: Leo <erbl259-lmu@yahoo.de>
Date: Tue, 6 Jul 2010 07:04:59 +0000
Subject: [PATCH] minor dram_read optimizations

git-svn-id: svn://cu.loc/avr-cpm/trunk@18 57430480-672e-4586-8877-bcf8adbbf3b7
---
 avrcpm/avr/Makefile |   4 +-
 avrcpm/avr/z80.asm  | 250 +++++++++++---------------------------------
 2 files changed, 65 insertions(+), 189 deletions(-)

diff --git a/avrcpm/avr/Makefile b/avrcpm/avr/Makefile
index 27b3b0c..b1a4afe 100644
--- a/avrcpm/avr/Makefile
+++ b/avrcpm/avr/Makefile
@@ -3,8 +3,8 @@
 # (GNU make, BSD make, SysV make)
 
 MCU = atmega8
-F_CPU = 12288000
-#BAUD = 38400
+#F_CPU = 12288000
+F_CPU = 20000000
 BAUD = 57600
 DRAM_DQ_ORDER = 1
 
diff --git a/avrcpm/avr/z80.asm b/avrcpm/avr/z80.asm
index f739512..1dca5ca 100755
--- a/avrcpm/avr/z80.asm
+++ b/avrcpm/avr/z80.asm
@@ -84,10 +84,14 @@
 .equ ram_a5 = 5
 .equ ram_a6 = 6
 .equ ram_a7 = 7
-.equ P_OE  = PORTD
 
-.equ RAM_AH_MASK = 0xE0             ; ram_a[7..5]
-.equ PD_OUTPUT_MASK = 0xFE
+.equ P_OE  = PORTD
+.equ P_AH  = PORTD
+.equ P_A8  = PORTD
+.equ P_MMC_CS = PORTD
+	             ; ram_a[7..5]
+.equ RAM_AH_MASK = (1<<ram_a8)|(1<<ram_a7)|(1<<ram_a6)|(1<<ram_a5)
+.equ PD_OUTPUT_MASK = (1<<mmc_cs) | (1<<ram_oe) | RAM_AH_MASK
 
 
 ;Port B
@@ -100,10 +104,13 @@
 .equ mmc_miso =	4
 .equ ram_ras =	5
 .equ mmc_sck =	5
+
 .equ P_RAS = PORTB
 
-.equ RAM_AL_MASK = 0x1F             ; ram_a[4..0]
-.equ PB_OUTPUT_MASK = 0x3F
+.equ P_AL  = PORTB
+			; ram_a[4..0]
+.equ RAM_AL_MASK = (1<<ram_a4)|(1<<ram_a3)|(1<<ram_a2)|(1<<ram_a1)|(1<<ram_a0)
+.equ PB_OUTPUT_MASK = (1<<ram_ras) | RAM_AL_MASK
 
 ;Port C
 #if DRAM_DQ_ORDER == 1
@@ -117,6 +124,8 @@
 .equ ram_d2 =	2
 .equ ram_d3 =	3
 .equ ram_cas=	5
+
+.equ P_DQ  = PORTC
 .equ P_W   = PORTC
 .equ P_CAS = PORTC
 
@@ -236,11 +245,11 @@ start:
 	ldi temp,PC_OUTPUT_MASK
 	out DDRC,temp
 
-	sbi PORTC,ram_w
-	sbi PORTC,ram_cas
-	sbi PORTB,ram_ras
-	sbi PORTD,ram_oe
-	sbi PORTD,mmc_cs
+	sbi P_W,ram_w
+	sbi P_CAS,ram_cas
+	sbi P_RAS,ram_ras
+	sbi P_OE,ram_oe
+	sbi P_MMC_CS,mmc_cs
 
 
 ; - Init serial port
@@ -983,7 +992,7 @@ mmcInit:
 	out SPCR,temp
 	
 	;Init start: send 80 clocks with cs disabled
-	sbi PORTD,mmc_cs
+	sbi P_MMC_CS,mmc_cs
 
 	ldi temp2,20
 mmcInitLoop:
@@ -992,21 +1001,21 @@ mmcInitLoop:
 	dec temp2
 	brne mmcInitLoop
 
-	cbi PORTD,mmc_cs
+	cbi P_MMC_CS,mmc_cs
 	rcall mmcByteNoSend
 	rcall mmcByteNoSend
 	rcall mmcByteNoSend
 	rcall mmcByteNoSend
 	rcall mmcByteNoSend
 	rcall mmcByteNoSend
-	sbi PORTD,mmc_cs
+	sbi P_MMC_CS,mmc_cs
 	rcall mmcByteNoSend
 	rcall mmcByteNoSend
 	rcall mmcByteNoSend
 	rcall mmcByteNoSend
 
 	;Send init command
-	cbi PORTD,mmc_cs
+	cbi P_MMC_CS,mmc_cs
 	ldi temp,0xff	;dummy
 	rcall mmcByte
 	ldi temp,0xff	;dummy
@@ -1029,7 +1038,7 @@ mmcInitLoop:
 	ldi temp2,0
 	rcall mmcWaitResp
 
-	sbi PORTD,mmc_cs
+	sbi P_MMC_CS,mmc_cs
 	rcall mmcByteNoSend
 
 
@@ -1038,7 +1047,7 @@ mmcInitLoop:
 mmcInitOcrLoop:	
 	push temp2
 
-	cbi PORTD,mmc_cs
+	cbi P_MMC_CS,mmc_cs
 	ldi temp,0xff	;dummy
 	rcall mmcByte
 	ldi temp,0x41	;cmd
@@ -1060,7 +1069,7 @@ mmcInitOcrLoop:
 	cpi temp,0
 	breq mmcInitOcrLoopDone
 
-	sbi PORTD,mmc_cs
+	sbi P_MMC_CS,mmc_cs
 	rcall mmcByteNoSend
 	
 	pop temp2
@@ -1073,7 +1082,7 @@ mmcInitOcrLoop:
 
 mmcInitOcrLoopDone:
 	pop temp2
-	sbi PORTD,mmc_cs
+	sbi P_MMC_CS,mmc_cs
 	rcall mmcByteNoSend
 
 	ldi temp,0
@@ -1087,7 +1096,7 @@ mmcReadSect:
 	ldi temp,0x50
 	out SPCR,temp
 
-	cbi PORTD,mmc_cs
+	cbi P_MMC_CS,mmc_cs
 	rcall mmcByteNoSend
 	ldi temp,0x51	;cmd (read sector)
 	rcall mmcByte
@@ -1130,7 +1139,7 @@ mmcreadloop:
 	rcall mmcByteNoSend
 	rcall mmcByteNoSend
 
-	sbi PORTD,mmc_cs
+	sbi P_MMC_CS,mmc_cs
 	rcall mmcByteNoSend
 
 	ldi temp,0
@@ -1144,7 +1153,7 @@ mmcWriteSect:
 	ldi temp,0x50
 	out SPCR,temp
 
-	cbi PORTD,mmc_cs
+	cbi P_MMC_CS,mmc_cs
 	rcall mmcByteNoSend
 
 	ldi temp,0x58	;cmd (write sector)
@@ -1197,7 +1206,7 @@ mmcwaitwritten:
 	cpi temp,0xff
 	brne mmcwaitwritten
 
-	sbi PORTD,mmc_cs
+	sbi P_MMC_CS,mmc_cs
 	rcall mmcByteNoSend
 
 	ldi temp,0
@@ -1426,46 +1435,10 @@ dram_write:
 
 ; ***************************** New DRAM routines ****************************
 
-; Defines how the dram nibbles are arganized.
-; RAMORG == 0 : A7 == 0: low nibble, A7 == 1: high nibble (Original Sprite_tm design)
-; RAMORG == 1 : A8 == 0: low nibble, A8 == 1: high nibble (faster)
-; 
-#define RAMORG 1
-
-#if RAMORG == 0
-;Sends the address in zh:zl to the ram
-dram_setaddr:
-	push temp
-	in temp,PORTB
-	andi temp,~RAM_AL_MASK
-	sbrc zl,0
-	 ori temp,(1<<ram_a0)
-	sbrc zl,1
-	 ori temp,(1<<ram_a1)
-	sbrc zl,2
-	 ori temp,(1<<ram_a2)
-	sbrc zl,3
-	 ori temp,(1<<ram_a3)
-	sbrc zl,4
-	 ori temp,(1<<ram_a4)
-	out PORTB,temp
-
-	in temp,PORTD
-	andi temp,~RAM_AH_MASK
-	sbrc zl,5
-	 ori temp,(1<<ram_a5)
-	sbrc zl,6
-	 ori temp,(1<<ram_a6)
-	sbrc zl,7
-	 ori temp,(1<<ram_a7)
-	sbrc zh,0
-	 ori temp,(1<<ram_a8)
-	out PORTD,temp
-	pop temp
-#else /* RAMORG == 1 */
+;todo: see below
 .macro DRAM_SETADDR
-	push temp
-	in temp,PORTB
+#if 1
+	in temp,P_AL
 	andi temp,~RAM_AL_MASK
 	sbrc @0,0
 	 ori temp,(1<<ram_a0)
@@ -1477,9 +1450,12 @@ dram_setaddr:
 	 ori temp,(1<<ram_a3)
 	sbrc @0,4
 	 ori temp,(1<<ram_a4)
-	out PORTB,temp
+	out P_AL,temp
+#else
+	out PORTB,@0
+#endif
 
-	in temp,PORTD
+	in temp,P_AH
 	andi temp,~RAM_AH_MASK
 	sbrc @0,5
 	 ori temp,(1<<ram_a5)
@@ -1487,19 +1463,9 @@ dram_setaddr:
 	 ori temp,(1<<ram_a6)
 	sbrc @0,7
 	 ori temp,(1<<ram_a7)
-	out PORTD,temp
-	pop temp
+	out P_AH,temp
 .endm
 	ret
-#endif /* RAMORG */
-
-.macro DRAM_SENDNIBBLE
-	in temp2,PORTC
-	andi temp2,~RAM_DQ_MASK
-	andi temp,RAM_DQ_MASK
-	or  temp2,temp
-	out PORTC,temp2
-.endm
 
 
 ;Loads the byte on address adrh:adrl into temp.
@@ -1507,67 +1473,30 @@ dram_setaddr:
 
 dram_read:
 	cli
-#if RAMORG == 0
-	mov zl,adrh
-	ldi zh,0
-	mov temp2,adrl
-	lsl temp2
-	rol zl
-	rol zh
-	;z=addr[15-7]
-	rcall dram_setaddr
-	cbi PORTB,ram_ras
-
-	ldi zh,0
-	mov zl,adrl
-	andi zl,0x7F
-	rcall dram_setaddr
-	cbi PORTC,ram_cas
-	cbi PORTD,ram_oe
-	ldi zh,0
-	in  temp,PINC
-	andi temp,0x0f
-	swap temp
-	sbi PORTC,ram_cas
-
-	mov zl,adrl
-	ori zl,0x80
-	rcall dram_setaddr
-	cbi PORTC,ram_cas
-	nop
-	in  temp2,PINC
-	andi temp2,0x0f
-	or  temp,temp2
-
-	sbi PORTD,ram_oe
-	sbi PORTC,ram_cas
-	sbi PORTB,ram_ras
-#else
-	cbi PORTD,ram_a8
+	cbi P_A8,ram_a8
 	DRAM_SETADDR adrh
-	cbi PORTB,ram_ras
+	cbi P_RAS,ram_ras
 
 	DRAM_SETADDR adrl
-	cbi PORTD,ram_oe
-	cbi PORTC,ram_cas
+	cbi P_CAS,ram_cas
+	cbi P_OE,ram_oe
 	nop
 	nop
-	in  temp,PINC
-	sbi PORTC,ram_cas
+	in  temp,P_DQ-2		; PIN
+	sbi P_CAS,ram_cas
 
-	sbi PORTD,ram_a8
-	cbi PORTC,ram_cas
+	sbi P_A8,ram_a8
+	cbi P_CAS,ram_cas
 	andi temp,0x0f
 	swap temp
-	in  temp2,PINC
+	in  temp2,P_DQ-2	; PIN
 	andi temp2,0x0f
 	or  temp,temp2
 	swap temp
 
-	sbi PORTD,ram_oe
-	sbi PORTC,ram_cas
-	sbi PORTB,ram_ras
-#endif
+	sbi P_OE,ram_oe
+	sbi P_CAS,ram_cas
+	sbi P_RAS,ram_ras
 	sei
 	ret
 
@@ -1577,87 +1506,34 @@ dram_read:
 
 dram_write:
 	cli
-#if RAMORG == 0
-	in temp2,DDRC               ;DRAM data ports as outputs
-	ori temp2,RAM_DQ_MASK
+	ldi temp2,RAM_DQ_MASK | (1<<ram_w) | (1<<ram_cas)
 	out DDRC,temp2
 
-	push temp
-	DRAM_SENDNIBBLE
-	pop temp
-
-	mov zl,adrh
-	ldi zh,0
-	mov temp2,adrl
-	lsl temp2
-	rol zl
-	rol zh
-	;z=addr[15-7]
-	rcall dram_setaddr
-	cbi PORTB,ram_ras
-
-	ldi zh,0
-	mov zl,adrl
-	ori zl,0x80
-	cbi PORTC,ram_w             ;early write
-	rcall dram_setaddr
-	cbi PORTC,ram_cas
-	sbi PORTC,ram_cas
-
-	ldi zh,0
-	mov zl,adrl
-	andi zl,0x7F
-	rcall dram_setaddr
-	swap temp
-
-	DRAM_SENDNIBBLE
-
-	cbi PORTC,ram_cas
-	sbi PORTC,ram_cas
-	sbi PORTC,ram_w
-	sbi PORTB,ram_ras
-
-	in temp,DDRC
-	andi temp,~RAM_DQ_MASK
-	out DDRC,temp
-	in temp,PORTC
-	andi temp,~RAM_DQ_MASK
+	mov  temp2,temp
+	andi temp,RAM_DQ_MASK & ~(1<<ram_w)
+	ori temp,(1<<ram_cas)
 	out PORTC,temp
-#else /* RAMORG == 1 */
-	in temp2,DDRC               ;DRAM data ports as outputs
-	ori temp2,RAM_DQ_MASK
-	out DDRC,temp2
-
-	push temp
-	DRAM_SENDNIBBLE
-	pop temp
 
 	cbi PORTD,ram_a8
 	DRAM_SETADDR adrh
-	cbi PORTB,ram_ras
-
-	cbi PORTC,ram_w             ;early write
+	cbi P_RAS,ram_ras
 	DRAM_SETADDR adrl
 	cbi PORTC,ram_cas
 	sbi PORTC,ram_cas
 
 	sbi PORTD,ram_a8
-	swap temp
+	swap temp2
 
-	DRAM_SENDNIBBLE
+	andi temp2,RAM_DQ_MASK & ~(1<<ram_w)
+	ori temp2,(1<<ram_cas)
+	out PORTC,temp2
 
 	cbi PORTC,ram_cas
-	sbi PORTC,ram_cas
-	sbi PORTC,ram_w
-	sbi PORTB,ram_ras
+	sbi P_RAS,ram_ras
 
-	in temp,DDRC
-	andi temp,~RAM_DQ_MASK
+	ldi temp,~RAM_DQ_MASK | (1<<ram_w) | (1<<ram_cas)
 	out DDRC,temp
-	in temp,PORTC
-	andi temp,~RAM_DQ_MASK
 	out PORTC,temp
-#endif /* RAMORG */
 	sei
 	ret
 
-- 
2.39.2