From f104746ebc76355f49aab97f01509eb8968b6241 Mon Sep 17 00:00:00 2001
From: FeralChild64 <you@example.com>
Date: Thu, 30 Jan 2020 22:37:42 +0100
Subject: [PATCH] small tape code optimization

---
 c64/kernal/banking/mega65_imports.s           |  7 -------
 c64/kernal/tape/load_tape_turbo.s             |  4 ----
 .../tape/tape_turbo_byte_store_mega65.s       | 19 -------------------
 c64/kernal/tape/tape_turbo_bytestore.s        | 17 ++++++++++++++++-
 4 files changed, 16 insertions(+), 31 deletions(-)
 delete mode 100644 c64/kernal/tape/tape_turbo_byte_store_mega65.s

diff --git a/c64/kernal/banking/mega65_imports.s b/c64/kernal/banking/mega65_imports.s
index 8546e2ce..d06b0bdb 100644
--- a/c64/kernal/banking/mega65_imports.s
+++ b/c64/kernal/banking/mega65_imports.s
@@ -55,10 +55,3 @@
 .label tape_normal_byte_store          = KERNAL_0.tape_normal_byte_store
 
 #endif
-
-
-#if CONFIG_TAPE_TURBO
-
-.label tape_turbo_byte_store           = KERNAL_0.tape_turbo_byte_store
-
-#endif
diff --git a/c64/kernal/tape/load_tape_turbo.s b/c64/kernal/tape/load_tape_turbo.s
index ab42535d..7c421e90 100644
--- a/c64/kernal/tape/load_tape_turbo.s
+++ b/c64/kernal/tape/load_tape_turbo.s
@@ -128,11 +128,7 @@ load_tape_turbo_payload:
 load_tape_turbo_loop:
 
 	jsr tape_turbo_get_byte
-#if ROM_LAYOUT_M65
-	jsr tape_turbo_byte_store
-#else
 	jsr __tape_turbo_bytestore         // like 'sta (MEMUSS),y' - but under I/O
-#endif
 
 	eor PRTY                           // handle checksum
 	sta PRTY
diff --git a/c64/kernal/tape/tape_turbo_byte_store_mega65.s b/c64/kernal/tape/tape_turbo_byte_store_mega65.s
deleted file mode 100644
index bfc4b77c..00000000
--- a/c64/kernal/tape/tape_turbo_byte_store_mega65.s
+++ /dev/null
@@ -1,19 +0,0 @@
-// #LAYOUT# M65 KERNAL_0 #TAKE
-// #LAYOUT# *   *        #IGNORE
-
-//
-// Tape (turbo) helper routine - byte storage when ban changing is needed
-//
-
-
-#if CONFIG_TAPE_TURBO
-
-
-tape_turbo_byte_store:
-
-	jsr map_NORMAL
-	jsr __tape_turbo_bytestore         // like 'sta (MEMUSS),y' - but under I/O
-	jmp map_KERNAL_1
-
-
-#endif
diff --git a/c64/kernal/tape/tape_turbo_bytestore.s b/c64/kernal/tape/tape_turbo_bytestore.s
index 25bf7a6b..03bd41f6 100644
--- a/c64/kernal/tape/tape_turbo_bytestore.s
+++ b/c64/kernal/tape/tape_turbo_bytestore.s
@@ -5,8 +5,10 @@
 //
 // Tape (turbo) helper routine - storing byte uder I/O
 //
+// Has to preserve .A and .Y
+//
 
-// This helper routine is meant to be copiet to the start of CPU stack.
+// This helper routine is meant to be copied to the start of CPU stack.
 // Original ROM tape loading routines uses this area to store information
 // about bytes that did not read properly for the first time
 // (see Mapping the C64, page 47); this mechanism is useless for turbo tape,
@@ -16,12 +18,20 @@
 #if CONFIG_TAPE_TURBO
 
 
+#if ROM_LAYOUT_M65
+.label __tape_turbo_bytestore_defmap  = __tape_turbo_bytestore + 10
+#else
 .label __tape_turbo_bytestore_defmap  = __tape_turbo_bytestore + 7
+#endif
 .label __tape_turbo_bytestore_size    = __tape_turbo_bytestore_source_end - tape_turbo_bytestore_source
 
 
 tape_turbo_bytestore_source:
 
+#if ROM_LAYOUT_M65
+	jsr KERNAL_0.map_NORMAL
+#endif
+
 	// Set all memory as RAM, tape motor ON
 	ldx #$00
 	stx CPU_R6510
@@ -33,8 +43,13 @@ tape_turbo_bytestore_source:
 	ldx #$00                           // value will be determined later, offset from start: 7 bytes
 	stx CPU_R6510
 
+#if ROM_LAYOUT_M65
+	// Restore default map and quit
+	jmp KERNAL_0.map_KERNAL_1
+#else
 	// Go back
 	rts
+#endif
 
 __tape_turbo_bytestore_source_end: