more I/O work in BASIC

c64/basic/basic_commands/cmd_load_verify.s

@@ -16,26 +16,19 @@ cmd_load:
 
 	lda #$00                           // mark operation as LOAD	
 	jsr helper_load_init_params
+	jsr helper_load_setnam_any         // if no file name found, use "*"
 
 	// Fetch the file name
 
 	jsr helper_load_fetch_filename
-	bcs cmd_load_no_filename
+	bcs !+
 
-	// Try to fetch device and secondary address
-
-	jsr fetch_device_secondary
-	jmp cmd_load_got_params
-
-cmd_load_no_filename:
-
-	// If no file name is supplied, try to load first file from disc
-
-	lda #$01                           // name length
-	ldx #<filename_any
-	ldy #>filename_any
-	jsr JSETNAM
+	// Try to fetch device number and secondary address
 
+	jsr helper_load_fetch_devnum
+	bcs !+
+	jsr helper_load_fetch_secondary
+!:
 	// FALLTROUGH
 
 cmd_load_got_params:                   // input for tape wedge

c64/basic/basic_commands/cmd_save.s

@@ -5,22 +5,22 @@
 
 cmd_save:
 
-	// Set default device and secondary address; channel is not important now
+	// Set default device and secondary address
 
-	jsr select_device
-	ldy #$00
-	jsr JSETFLS
+	jsr helper_load_init_params_no_VERCKB
 
 	// Fetch the file name
 
 	jsr helper_load_fetch_filename
 	bcs_16 do_MISSING_FILENAME_error
 
-	// Try to fetch device
+	// Try to fetch device number and secondary address
 
-	jsr fetch_device_secondary
-
-	// Setup the start and end addresses
+	jsr helper_load_fetch_devnum
+	bcs !+
+	jsr helper_load_fetch_secondary
+!:
+	// Setup the start address
 
 	lda #TXTTAB
 
@@ -29,6 +29,10 @@ cmd_save:
 	ldx VARTAB+0
 	ldy VARTAB+1
 
+	// FALLTROUGH
+
+cmd_save_do: // entry point for BSAVE
+
 	// Perform saving
 
 	jsr JSAVE

c64/basic/basic_commands/helper_load_fetch_devnum.s

@@ -0,0 +1,20 @@
+// #LAYOUT# STD *       #TAKE
+// #LAYOUT# *   BASIC_0 #TAKE
+// #LAYOUT# *   *       #IGNORE
+
+
+//
+// Tries to fetch device number - sets Carry if failure
+//
+
+
+helper_load_fetch_devnum:
+
+	// Fetch the device number
+
+	jsr fetch_coma_uint8
+	bcs !+
+
+	sta FA
+!:
+	rts

c64/basic/basic_commands/helper_load_fetch_secondary.s

@@ -0,0 +1,20 @@
+// #LAYOUT# STD *       #TAKE
+// #LAYOUT# *   BASIC_0 #TAKE
+// #LAYOUT# *   *       #IGNORE
+
+
+//
+// Tries to fetch secondary address - sets Carry if failure
+//
+
+
+helper_load_fetch_secondary:
+
+	// Fetch the device number
+
+	jsr fetch_coma_uint8
+	bcs !+
+
+	sta SA
+!:
+	rts

c64/basic/basic_commands/helper_load_init_param.s

@@ -16,6 +16,10 @@ helper_load_init_params:
 
 	sta VERCKB
 
+	// FALLTROUGH
+
+helper_load_init_params_no_VERCKB:
+
 	// Set default device, set secondary address to 0
 
 	jsr select_device

c64/basic/basic_commands/helper_load_setnam_any.s

@@ -0,0 +1,15 @@
+// #LAYOUT# STD *       #TAKE
+// #LAYOUT# *   BASIC_0 #TAKE
+// #LAYOUT# *   *       #IGNORE
+
+//
+// Set '*' as file name
+//
+
+
+helper_load_setnam_any:
+
+	lda #$01                           // name length
+	ldx #<filename_any
+	ldy #>filename_any
+	jmp JSETNAM

c64/basic/basic_commands_CC/cmd_bsave.s

@@ -5,4 +5,53 @@
 
 cmd_bsave:
 
-	jmp do_NOT_IMPLEMENTED_error // XXX implement the command
+	// Set default device and secondary address
+
+	jsr helper_load_init_params_no_VERCKB
+
+	// Fetch the file name
+
+	jsr helper_load_fetch_filename
+	bcs_16 do_MISSING_FILENAME_error
+
+	// Fetch device number
+
+	jsr injest_comma
+	bcs_16 do_SYNTAX_error
+	jsr helper_load_fetch_devnum
+	bcs_16 do_SYNTAX_error
+
+	// Fetch memory area start address
+
+	jsr injest_comma
+	bcs_16 do_SYNTAX_error
+
+	jsr basic_parse_line_number                  // XXX detect errors here
+
+	lda LINNUM+0
+	pha
+	lda LINNUM+1
+	pha
+
+	// Fetch memory area end address
+
+	jsr injest_comma
+	bcs_16 do_SYNTAX_error
+
+	jsr basic_parse_line_number                  // XXX detect errors here
+
+	// Setup start/end addresses
+
+	ldx LINNUM+0
+	ldy LINNUM+1
+
+	pla
+	sta LINNUM+1
+	pla
+	sta LINNUM+0
+
+	lda #LINNUM
+
+	// Perform SAVE - reuse regular command
+
+	jmp cmd_save_do

c64/basic/basic_commands_CC/cmd_merge.s

@@ -24,11 +24,8 @@ cmd_merge:
 !:
 	// Fetch device number
 
-	jsr fetch_coma_uint8
-	bcs !+
+	jsr helper_load_fetch_devnum
 
-	sta FA
-!:
 	// Perform loading - just for a different address
 
 	sec

c64/basic/engine/fetch_uint8.s

@@ -17,8 +17,7 @@ fetch_coma_uint8:
 fetch_uint8:
 
 	jsr injest_spaces
-	jsr basic_parse_line_number
-	// XXX this should also detect errors
+	jsr basic_parse_line_number                  // XXX detect errors here
 	lda LINNUM+1
 	bne_16 do_ILLEGAL_QUANTITY_error
 	lda LINNUM+0