more compatible STAL/EAL/MEMUSS handling

c64/kernal/iec/load_iec.s

@@ -69,20 +69,23 @@ load_iec:
 	jsr iec_turnaround_to_listen
 	bcs load_iec_error
 
-	// Get load address and store it if secondary address is zero
+	// Get load address
+
 	jsr iec_rx_byte
 	bcs load_iec_file_not_found
-
-	ldx SA
-	beq !+
-	sta STAL+0
-!:
+	sta EAL+0
 	jsr iec_rx_byte
 	bcs load_iec_file_not_found
+	sta EAL+1
 
-	ldx SA
-	beq !+
-	sta STAL+1
+	// If secondary address is 0, override EAL with STAL
+
+	lda SA
+	bne !+
+	lda STAL+0
+	sta EAL+0
+	lda STAL+1
+	sta EAL+1	
 !:
 	// Display start address
 	jsr lvs_display_loading_verifying
@@ -102,7 +105,7 @@ iec_load_loop:
 	
 	// Handle STOP key; it is probably an overkill to do it
 	// with every byte, once per 32 bytes should be enough
-	lda STAL
+	lda EAL
 	and #$1F
 	bne !+
 	phx_trash_a

c64/kernal/iec/save_iec.s

@@ -5,7 +5,7 @@
 
 
 // XXX this is untested!
-// test EAL/STAL - LOAD (tape, disk), SAVE - Open ROMs vs hybrid vs original
+// also test STAL/EAL - Open ROMs vs hybrid vs original
 
 
 

c64/kernal/iostack/load_save_common.s

@@ -22,7 +22,7 @@ lvs_handle_byte_load_verify:
 	ldx #$33
 	stx $01
 	ldy #0
-	sta (STAL),y
+	sta (EAL),y
 	ldx #$37
 	stx $01
 	plp
@@ -30,7 +30,7 @@ lvs_handle_byte_load_verify:
 #else
 
 	ldy #0
-	sta (STAL),y
+	sta (EAL),y
 
 #endif
 
@@ -55,7 +55,7 @@ lvs_handle_byte_verify:
 	ldx #$33
 	stx $01
 	ldy #0
-	lda (STAL),y
+	lda (EAL),y
 	ldx #$37
 	stx $01
 	plp
@@ -66,7 +66,7 @@ lvs_handle_byte_verify:
 #else
 
 	ldy #0
-	cmp (STAL),y
+	cmp (EAL),y
 
 #endif
 
@@ -79,9 +79,9 @@ lvs_handle_byte_verify:
 lvs_advance_pointer:
 
 	// Advance pointer
-	inc STAL+0
+	inc EAL+0
 	bne !+
-	inc STAL+1
+	inc EAL+1
 !:
 	rts
 
@@ -135,9 +135,9 @@ lvs_display_start_addr:
 !:
 	jsr print_kernal_message
 
-	lda STAL+1
+	lda EAL+1
 	jsr print_hex_byte
-	lda STAL+0
+	lda EAL+0
 	jmp print_hex_byte
 
 lvs_display_done:
@@ -181,8 +181,8 @@ lvs_return_last_address:
 
 	// Return last address - Compute's Mapping the 64 says without the '+1',
 	// checked (short test program) on original ROMs that this is really the case
-	ldx STAL+0
-	ldy STAL+1
+	ldx EAL+0
+	ldy EAL+1
 	// FALLTHROUGH
 
 lvs_success_end:

c64/kernal/tape/load_tape_turbo.s

@@ -61,36 +61,45 @@ load_tape_turbo_header_loop:           // this strange loop puts metadata after
 
 load_tape_turbo_payload:
 
+	// Initial checksum value
+
+	lda #$00
+	sta PRTY
+
 	// Read file payload
 
 	jsr tape_turbo_sync_payload
 
-	ldy #$00
-	sty PRTY                           // initial checksum value
-
 	// FALLTROUGH
 
 load_tape_turbo_loop:
 
 	jsr tape_turbo_get_byte
-	sta (STAL),y
+	sta (MEMUSS),y
 
 	eor PRTY                           // handle checksum
 	sta PRTY
 
-	jsr lvs_advance_pointer
-
-	lda STAL+1
+	// Advance MEMUSS (see Mapping the C64, page 36)
+	inc MEMUSS+0
+	bne !+
+	inc MEMUSS+1
+!:
+	lda MEMUSS+1
 	cmp EAL+1
 	bne load_tape_turbo_loop
-	lda STAL+0
+	lda MEMUSS+0
 	cmp EAL+0
 	bne load_tape_turbo_loop
 
-	// Verify the checksum
+	// Get the checksum
 
 	jsr tape_turbo_get_byte
-	cmp PRTY
+	tax
+
+	// Verify the checksum
+
+	cpx PRTY
 	beq_far tape_load_success
 	jmp tape_load_error
 

c64/kernal/tape/tape_common.s

@@ -208,9 +208,29 @@ tape_handle_header:
 	adc STAL+1
 	sta EAL+1
 !:
-	// Print LOADING
+	// Setup MEMUSS (see Mapping the C64, page 36)
 
-	jsr lvs_display_loading_verifying
+	lda STAL+0
+	sta MEMUSS+0
+	lda STAL+1
+	sta MEMUSS+1
+
+	// Print LOADING and start address
+
+	lda MSGFLG
+	bpl tape_handle_header_displayed
+
+	ldx #__MSG_KERNAL_LOADING
+	jsr print_kernal_message
+	ldx #__MSG_KERNAL_FROM_HEX
+	jsr print_kernal_message
+
+	lda STAL+1
+	jsr print_hex_byte
+	lda STAL+0
+	jsr print_hex_byte
+
+tape_handle_header_displayed:
 
 	// Load the file