From 4b2d99a399d97342e753d53c656df6aa120cf62b Mon Sep 17 00:00:00 2001
From: FeralChild64 <you@example.com>
Date: Wed, 28 Oct 2020 21:50:36 +0100
Subject: [PATCH] more work on SD card support on MEGA65

---
 src/dos_m65/,aliases_dos.s              |  4 +--
 src/dos_m65/sdcard/sdcard_init.s        | 13 +++++---
 src/dos_m65/sdcard/sdcard_writesector.s | 42 ++++++++++++++++++++++---
 3 files changed, 48 insertions(+), 11 deletions(-)

diff --git a/src/dos_m65/,aliases_dos.s b/src/dos_m65/,aliases_dos.s
index 954435dd..9a00472e 100644
--- a/src/dos_m65/,aliases_dos.s
+++ b/src/dos_m65/,aliases_dos.s
@@ -31,8 +31,8 @@
     !addr CARD_TMP_STEP    = $12 ; 4 bytes
     !addr CARD_TMP_RETRIES = $16 ; 1 byte
 
-    !addr CARD_BUFPNT      = $FC ; 4 bytes - pointer to hardware sector buffer  XXX replace copy routines with DMAgic
-
+    !addr CARD_BUFPNT1     = $17 ; 4 bytes - pointer to hardware sector buffer  XXX replace copy routines with DMAgic
+    !addr CARD_BUFPNT2     = $1B ; 4 bytes - as above, but points to the 2nd page of the hardware buffer
 
 
 	;
diff --git a/src/dos_m65/sdcard/sdcard_init.s b/src/dos_m65/sdcard/sdcard_init.s
index 9ed9878d..37cb383b 100644
--- a/src/dos_m65/sdcard/sdcard_init.s
+++ b/src/dos_m65/sdcard/sdcard_init.s
@@ -18,13 +18,18 @@ sdcard_init:
 	sta CARD_IS_SDHC
 
 	lda #SD_SECBUF_0
-	sta CARD_BUFPNT+0
+	sta CARD_BUFPNT1+0
+	sta CARD_BUFPNT2+0
 	lda #SD_SECBUF_1
-	sta CARD_BUFPNT+1
+	sta CARD_BUFPNT1+1
+	inc
+	sta CARD_BUFPNT2+1
 	lda #SD_SECBUF_2
-	sta CARD_BUFPNT+2
+	sta CARD_BUFPNT1+2
+	sta CARD_BUFPNT2+2
 	lda #SD_SECBUF_3
-	sta CARD_BUFPNT+3
+	sta CARD_BUFPNT1+3
+	sta CARD_BUFPNT2+3
 
 	; Reset the card
 
diff --git a/src/dos_m65/sdcard/sdcard_writesector.s b/src/dos_m65/sdcard/sdcard_writesector.s
index 833719fe..e4e1ac25 100644
--- a/src/dos_m65/sdcard/sdcard_writesector.s
+++ b/src/dos_m65/sdcard/sdcard_writesector.s
@@ -99,13 +99,47 @@ sdcard_writesector_verify:
 	and #$03
 	bne @3
 
-	; XXX verify - compare buffer
+	; FALLTROUGH
 
+sdcard_writesector_verify_loop:
 
+	; Compare buffers
 
+	phx
+	phz
 
+	ldx #$00
+	ldz #$00
 
+	lda [CARD_BUFPNT1],z
+	cmp CARD_BUF, x
+	bne sdcard_writesector_verify_fail
+	
+	lda [CARD_BUFPNT2],z
+	cmp CARD_BUF+$100, x
+	bne sdcard_writesector_verify_fail
 
+	inz
+	inx
+	bne sdcard_writesector_verify_loop
+
+	; FALLTROUGH
+
+sdcard_writesector_verify_success:
+
+	plz
+	plx
+
+	clc
+	rts
+
+sdcard_writesector_verify_fail:
+
+	plz
+	plx
+
+	sec
+	rts
 
 
 ;
@@ -124,11 +158,9 @@ sdcard_writesector_copy_data:
 
 @1:
 	lda CARD_BUF,x
-	sta [CARD_BUFPNT],z
-	inc CARD_BUFPNT+1
+	sta [CARD_BUFPNT1],z
 	lda CARD_BUF+$100,x
-	sta [CARD_BUFPNT],z
-	dec CARD_BUFPNT+1	
+	sta [CARD_BUFPNT2],z
 
 	inz
 	inx