dev: added signon strings and some other basic bootup code

.gitignore

@@ -11,6 +11,6 @@
 *.srec
 *.s19
 *.elf
-
+*.map
 AGENTS.md
 .pre-commit-config.yaml

Makefile

@@ -2,12 +2,16 @@
 # SPDX-FileCopyrightText: (c) 2025 A.M. Rowsell
 ASM=vasm_z80_std
 LINK=vlink
+MAP=zone.map
 
 ASMFLAGS=-Fvobj
-LINKFLAGS=-b ihex -T linker.cmd
+LINKFLAGS=-b ihex -T linker.cmd -M
+BINLINKFLAGS=-b rawbin -T linker.cmd -M
 
 all: zone.hex
 
+binary: zone.bin
+
 float.o: float.asm
 	$(ASM) $(ASMFLAGS) -o $@ $<
 
@@ -21,9 +25,12 @@ boot.o: boot.asm
 	$(ASM) $(ASMFLAGS) -o $@ $<
 
 zone.hex: float.o vectorTable.o zone.o boot.o linker.cmd
-	$(LINK) $(LINKFLAGS) -o $@ float.o vectorTable.o zone.o boot.o
+	$(LINK) $(LINKFLAGS) -o $@ float.o vectorTable.o zone.o boot.o > $(MAP)
+
+zone.bin: float.o vectorTable.o zone.o boot.o linker.cmd
+	$(LINK) $(BINLINKFLAGS) -o $@ float.o vectorTable.o zone.o boot.o > $(MAP)
 
 clean:
-	rm -f float.o vectorTable.o zone.o boot.o zone.hex
+	rm -f float.o vectorTable.o zone.o boot.o zone.hex zone.bin $(MAP)
 
 .PHONY: all clean

boot.asm

@@ -1,13 +1,20 @@
-; SPDX-License-Identifier: MPL-2.0
-; SPDX-FileCopyrightText: (c) 2025 A.M. Rowsell
-.section "boot","acrx"
-.global zone_setup
-.global os_warm_boot
-.extern os_main_loop
+	;        SPDX-License-Identifier: MPL-2.0
+	;        SPDX-FileCopyrightText: (c) 2025 A.M. Rowsell
+	.section "boot", "acrx"
+	.global  zone_setup
+	.global  os_warm_boot
+	.extern  os_main_loop
 
+	; ==================================
+	; This is the cold boot entry point!
+	; It is linked to land at 0xC3C3
+	; ==================================
+
+_start:
 zone_setup:
-    ld sp, 0x6FFF
-    jp os_main_loop
+	ld a, ixl
+	ld sp, 0x6FFF
+	jp os_main_loop
 
 os_warm_boot:
-    ret
+	ret

linker.cmd

@@ -2,10 +2,10 @@
 /* SPDX-FileCopyrightText: (c) 2025 A.M. Rowsell */
 SECTIONS
 {
-  .zone     0xA000 : { *(.zone) *(zone) }
+  .zone     0xA000 : { zone.o(zone) float.o(zone) *(.zone) *(zone) }
   .boot     0xC3C3 : { *(.boot) *(boot) }
-  .text     0xE000 : { *(.text) *(.float) *(float) }
   .vectors  0xF000 : { *(.vectors) }
   .data     0x7000 : { *(.data) }
-  .bss            : { *(.bss)  }
+  __data_end = .;
+  .bss      __data_end : { *(.bss)  }
 }

zone.asm

@@ -1,30 +1,135 @@
-; SPDX-License-Identifier: MPL-2.0
-; SPDX-FileCopyrightText: (c) 2025 A.M. Rowsell
-; ============================================================
-; ZONE OS main section
-; ============================================================
-.section "zone","acrx"
-.global zone_start
-.global os_print_vec
-.global os_getch_vec
-.global os_outbyte_vec
-.global os_inbyte_vec
-.global os_main_loop
+	;        SPDX-License-Identifier: MPL-2.0
+	;        SPDX-FileCopyrightText: (c) 2025 A.M. Rowsell
+	;        ============================================================
+	;        ZONE OS main section
+	;        ============================================================
+	.section "zone", "acrx"
+	.global  os_print_vec
+	.global  os_getch_vec
+	.global  os_outbyte_vec
+	.global  os_inbyte_vec
+	.global  os_main_loop
+	.local   os_print_signon
 
-zone_start:
-    ret
+	.set UARTSTATUS, 6
+	.set UARTDATA, 7
 
 os_print_vec:
-    ret
+	;    this takes a character in a and sends it to the UART
+	push af
+	push bc
+	push de
+	ld   d, a
+	ld   c, UARTSTATUS
+
+$1:
+	in  a, (c); get status byte
+	bit 0, a; test bit 0
+	jr  z, $1; jump back if UART not ready
+	ld  a, d
+	ld  c, UARTDATA
+	out (c), a; send byte to uart
+	pop de
+	pop bc
+	pop af
+	ret
 
 os_getch_vec:
-    ret
+	;    this gets a character from the UART and puts in in a
+	push bc
+	ld   c, UARTSTATUS
+
+a2:
+	in  a, (c); get status byte
+	bit 1, a
+	jr  z, a2
+	ld  c, UARTDATA
+	in  a, (c)
+	pop bc
+	ret
 
 os_outbyte_vec:
-    ret
+	;    this takes a byte in a and sends it to port in hl
+	push af
+	push bc
+	push hl
+	ld   c, l
+	out  (c), a
+	pop  hl
+	pop  bc
+	pop  af
+	ret
 
 os_inbyte_vec:
-    ret
+	;    this gets a byte from port in hl and returns it in a
+	push bc
+	push hl
+	ld   c, l
+	in   a, (c)
+	pop  hl
+	pop  bc
+	ret
 
 os_main_loop:
-    jp os_main_loop
+	call os_print_signon
+
+os_busy_loop:
+	jp os_busy_loop
+
+	; ======================
+	; non-vectored functions
+	; ======================
+
+os_print_signon:
+	ld hl, zoneSignon
+	ld a, (hl)
+
+$2:
+	call os_print_vec
+	inc  hl
+	ld   a, (hl)
+	jr   nz, $2
+
+$3:
+	ld hl, zoneCopyright
+	ld a, (hl)
+
+$4:
+	call os_print_vec
+	inc  hl
+	ld   a, (hl)
+	jr   nz, $4
+	ret
+
+zoneSignon:
+	.byte "ZONE OS ver. 0.01"
+	.byte 10, 13, 0
+
+zoneCopyright:
+	.byte "(c) A.M. Rowsell, license MPLv2"
+	.byte 10, 13, 0
+
+zonePrompt:
+	.string "z] "
+
+	; error messages
+
+errorSyntax:
+	.string "Syntax error!"
+
+errorTimeout:
+	.string "Command timed out."
+
+errorNotFound:
+	.string "Command/file not found."
+
+errorHardware:
+	.string "Hardware error!"
+
+errorRAMFailed:
+	.string "RAM test failed!"
+
+stringTable:
+	.word zoneSignon, zoneCopyright, zonePrompt
+	.word errorSyntax, errorTimeout, errorNotFound
+	.word errorHardware, errorRAMFailed