progress on FAT16 support

OperatingSystem/monitor_v2/include/.old/bootldr.s

@@ -0,0 +1,115 @@
+; Z8C Bootloader
+; 2022 by Dennis Gunia
+
+BTLDR_ENTRY:    
+                ;ld SP, 0ffffh       ; set stack pointer
+
+                ;Setup Serial Interface
+                LD A,01001111b      ; External Trigger, Time Constant Follows
+                OUT (CS_CTC_0),A    
+                IN A,(CS_DIP)       ; Read BAUD from DIP-Switches
+                OUT (CS_CTC_0),A
+                LD A,00110000b      ;write into WR0: error reset, select WR0
+                OUT (CS_SIO_A_C),A
+                LD a,018h           ;write into WR0: channel reset
+                OUT (CS_SIO_A_C),A
+                LD a,004h           ;write into WR0: select WR4
+                OUT (CS_SIO_A_C),A
+                ;LD a,04h            ;write into WR4: clkx1,1 stop bit, no parity
+                LD a,01000100b       ;write into WR4: clkx16,1 stop bit, no parity
+                OUT (CS_SIO_A_C),A
+                LD a,005h ;write into WR0: select WR5
+                OUT (CS_SIO_A_C),A
+                LD a,11101000b ;DTR inactive, TX 8bit, BREAK off, TX on, RTS inactive
+                OUT (CS_SIO_A_C),A
+                LD a,01h ;write into WR0: select WR1
+                OUT (CS_SIO_A_C),A
+                LD a,00000100b ;no interrupt in CH B, special RX condition affects vect
+                OUT (CS_SIO_A_C),A
+                LD a,02h ;write into WR0: select WR2
+                OUT (CS_SIO_A_C),A
+                LD a,0h ;write into WR2: cmd line int vect (see int vec table)
+                        ;bits D3,D2,D1 are changed according to RX condition
+                OUT (CS_SIO_A_C),A
+                LD a,003h ;write into WR0: select WR3
+                OUT (CS_SIO_A_C),A
+                LD a,0C1h ;RX 8bit, auto enable off, RX on
+                OUT (CS_SIO_A_C),A
+
+BTLDR_STARTUP_MSG:
+                LD HL,[S_BTLDR_STARTUP_MSG]
+    BTLDR_STARTUP_MSG_LOOP:
+                LD A,(HL)
+                OR A
+                JR Z, BTLDR_INPUT
+                CALL BTLDR_SUB_WRITEA
+                INC HL
+                JR BTLDR_STARTUP_MSG_LOOP
+BTLDR_INPUT:
+        ; Byte 1 & 2 = Length
+        CALL BTLDR_SUB_INPUT_READ
+        LD B, A
+        CALL BTLDR_SUB_INPUT_READ
+        LD C, A
+        
+        ; Byte 3 & 4 = Offset / Start address
+        CALL BTLDR_SUB_INPUT_READ
+        LD H, A
+        CALL BTLDR_SUB_INPUT_READ
+        LD L, A
+
+        ; Byte 5+ = Payload
+    BTLDR_INPUT_1:
+        CALL BTLDR_SUB_INPUT_READ
+        LD (HL),A   ;Store byte
+        DEC BC
+        LD A,H
+        OR A.L
+        JR Z, BTLDR_DONE
+        INC HL
+        JR BTLDR_INPUT_1
+        
+BTLDR_DONE:
+    RET
+
+
+; Strings
+S_BTLDR_STARTUP_MSG:
+    db "Z8C BTLDR.S V0.1 by Dennis Gunia [RDY] ",0
+
+
+; Subroutines
+BTLDR_SUB_WRITEA:
+                OUT (CS_SIO_A_D),A
+    BTLDR_SUB_WRITEA_WAIT:
+                XOR A
+                INC A
+                OUT (CS_SIO_A_C),A
+                IN A,(CS_SIO_A_C) 
+                BIT 0,A
+                JR Z, BTLDR_SUB_WRITEA_WAIT
+                RET
+
+BTLDR_SUB_RTS_OFF:
+    ld a,005h ;write into WR0: select WR5
+    out (CS_SIO_A_C),A
+    ld a,0E8h ;DTR active, TX 8bit, BREAK off, TX on, RTS inactive
+    out (CS_SIO_A_C),A
+    ret
+BTLDR_SUB_RTS_ON:
+    ld a,005h ;write into WR0: select WR5
+    out (CS_SIO_A_C),A
+    ld a,0EAh ;DTR active, TX 8bit, BREAK off, TX on, RTS active
+    out (CS_SIO_A_C),A
+    ret
+
+BTLDR_SUB_INPUT_READ:
+    CALL BTLDR_SUB_RTS_ON
+    XOR A
+    OUT (CS_SIO_A_C), a
+    IN A, (CS_SIO_A_C)
+    AND 1
+    JR Z, BTLDR_SUB_INPUT_READ  ;LOOP IF BUFFER EMPTY
+    CALL BTLDR_SUB_RTS_OFF
+    IN A, (CS_SIO_A_D)
+    RET

OperatingSystem/monitor_v2/include/.old/debug.s

@@ -0,0 +1,78 @@
+
+
+debug_init:
+    ld A,VAR_CONSOLE_CONF   ; Setup CTC
+    out (IO_CTC0_C0),A      ; Controll word, software reset, time constant follows, CLK/TRG starts timer
+    ld A,VAR_CONSOLE_BAUD   ; Setup timer const
+    out (IO_CTC0_C0),A      ; Load timer const into CTC (Setup Baud generator)
+    ;set up TX and RX:W
+    ld a,00110000b      ;write into WR0: error reset, select WR0
+    out (IO_SIO0A_C),A
+    ld a,018h           ;write into WR0: channel reset
+    out (IO_SIO0A_C),A
+    ld a,004h           ;write into WR0: select WR4
+    out (IO_SIO0A_C),A
+    ld a,04h            ;44h write into WR4: clkx1,1 stop bit, no parity
+    out (IO_SIO0A_C),A
+    ld a,005h           ;write into WR0: select WR5
+    out (IO_SIO0A_C),A
+    ld a,068h           ;DTR active, TX 8bit, BREAK off, TX on, RTS inactive
+    out (IO_SIO0A_C),A
+    ld a,01h            ;write into WR0: select WR1
+    out (IO_SIO0A_C),A
+    ld a,00000100b      ;no interrupt in CH B, special RX condition affects vect
+    out (IO_SIO0A_C),A
+    ;enable SIO channel A RX
+    ld a,003h ;write into WR0: select WR3
+    out (IO_SIO0A_C),A
+    ld a,0C1h ;RX 8bit, auto enable off, RX on
+    out (IO_SIO0A_C),A
+    ;Channel A RX active
+    ld hl,[MSG_START_DBG]
+    call debug_print_str
+    ret
+
+debug_print_char:
+    out (IO_SIO0A_D),a
+    call debug_wait_out
+    ret
+
+debug_print_str:
+    ld a, (hl)
+    or a
+    ret z
+    call debug_print_char
+    inc hl
+    jr debug_print_str
+
+debug_print_newLine:
+    ld a,10
+    call debug_print_char
+    ld a,13
+    call debug_print_char
+    ret
+
+debug_wait_out:
+    ; check for TX buffer empty
+    sub a ;clear a, write into WR0: select RR0
+    inc a ;select RR1
+    out (IO_SIO0A_C),A
+    in A,(IO_SIO0A_C) ;read RRx
+    bit 0,A
+    jr z,debug_wait_out
+    ret
+
+MSG_START_DBG:
+    db "Debug interface active!",13,10,0
+
+debug_a_hex:
+    push BC
+    push AF
+    call STRCONV_BYTES_TO_HEX
+    ld a, b
+    call debug_print_char
+    ld a, c
+    call debug_print_char
+    pop AF
+    pop BC
+    ret

OperatingSystem/monitor_v2/include/.old/disassembler copy.s

@@ -0,0 +1,322 @@
+; HL contains start address
+; B  contains length
+disassemble:
+    call dasm_print16hex_addr   ;print address  (HL)
+    call disassemble_table_seek
+    xor a
+    or b
+    or c
+    jr z, disassemble_err   ;if bc==0000h
+
+    ld a,(hl)   ;load first byte
+
+
+
+
+
+    call dasm_print8hex         ;print value
+    ld a,(hl)
+    cp 0xC3         ;C3 JPnn
+    jp z, dasm_C3
+
+    ;start getting value
+
+disassemble_err:
+    ld a,(hl)
+    call dasm_print8hex         ;print value
+    push hl
+    ld hl, [dasm_UU]
+    call print_str
+    pop hl
+disassemble_continue:
+    call print_newLine
+    inc hl
+    dec b
+    jp nz, disassemble
+    ret
+
+
+
+;A contains char
+;BC contains returned position
+disassemble_table_seek:
+    push hl
+    ld c,a
+disassemble_table_seek_loop:
+    ld a,(hl)
+    cp c    ; if match
+    jr z, disassemble_table_found
+    or a    ; if null
+    jp z, disassemble_table_notfound
+    ld b,0
+    ld c,4
+    add hl,bc
+    ld a,(hl)
+    ld c,a
+    add hl,bc
+    inc hl
+    jr disassemble_table_seek_loop
+
+
+disassemble_table_found
+    ld b,H
+    ld c,l
+    pop hl
+    ret
+
+disassemble_table_notfound
+    ld b,0
+    ld c,0
+    pop hl
+    ret
+
+
+
+dasm_C3: ;JP nn (276)
+    inc hl
+    ld e, (HL)
+    inc hl
+    ld d, (HL)
+    inc hl
+    ;de now has jmp value
+    push hl
+    ld hl, [dasm_C3_str]
+    call print_str
+    ld h,d
+    ld l,e
+    call dasm_print16hex_addr
+    pop hl
+    jp disassemble_continue
+dasm_C3_str:
+    db "JP ",0x00
+
+dasm_JPccnn: ;JP nn (276)
+    rra
+    rra
+    rra
+    and 0x07
+    call dasm_printFlags
+    ld a, ","
+    call print_char
+    inc hl
+    ld e, (HL)
+    inc hl
+    ld d, (HL)
+    inc hl
+    ;de now has jmp value
+    push hl
+    ld hl, [dasm_C3_str]
+    call print_str
+    ld h,d
+    ld l,e
+    call dasm_print16hex_addr
+    pop hl
+    jp disassemble_continue
+
+dasm_18: ;JR e
+    inc hl
+    ld e, (HL)
+    inc hl
+    ;de now has jmp value
+    push hl
+    ld hl, [dasm_18_str]
+    call print_str
+    ld a,e
+    call dasm_print8relhex
+    pop hl
+    jp disassemble_continue
+dasm_18_str:
+    db "JR ",0x00
+
+dasm_38: ;JR C,e
+    inc hl
+    ld e, (HL)
+    inc hl
+    ;de now has jmp value
+    push hl
+    ld hl, [dasm_38_str]
+    call print_str
+    ld a,e
+    call dasm_print8relhex
+    pop hl
+    jp disassemble_continue
+dasm_38_str:
+    db "JR C, ",0x00
+
+dasm_30: ;JR NC,e
+    inc hl
+    ld e, (HL)
+    inc hl
+    ;de now has jmp value
+    push hl
+    ld hl, [dasm_30_str]
+    call print_str
+    ld a,e
+    call dasm_print8relhex
+    pop hl
+    jp disassemble_continue
+dasm_30_str:
+    db "JR NC, ",0x00
+
+dasm_28: ;JR Z,e
+    inc hl
+    ld e, (HL)
+    inc hl
+    ;de now has jmp value
+    push hl
+    ld hl, [dasm_28_str]
+    call print_str
+    ld a,e
+    call dasm_print8relhex
+    pop hl
+    jp disassemble_continue
+dasm_28_str:
+    db "JR Z, ",0x00
+
+dasm_20: ;JR NZ,e
+    inc hl
+    ld e, (HL)
+    inc hl
+    ;de now has jmp value
+    push hl
+    ld hl, [dasm_20_str]
+    call print_str
+    ld a,e
+    call dasm_print8relhex
+    pop hl
+    jp disassemble_continue
+dasm_20_str:
+    db "JR NZ, ",0x00
+
+dasm_E9: ;JR NZ,e
+    inc hl
+    push hl
+    ld hl, [dasm_20_str]
+    call print_str
+    pop hl
+    jp disassemble_continue
+dasm_E9_str:
+    db "JP (HL), ",0x00
+
+dasm_E9: ;JP (HL)
+    inc hl
+    push hl
+    ld hl, [dasm_E9_str]
+    call print_str
+    pop hl
+    jp disassemble_continue
+dasm_E9_str:
+    db "JP (HL)",0x00
+
+dasm_E9: ;JP (IX)
+    inc hl
+    push hl
+    ld hl, [dasm_E9_str]
+    call print_str
+    pop hl
+    jp disassemble_continue
+dasm_E9_str:
+    db "JP (IX)",0x00
+
+dasm_E9: ;JP (IY)
+    inc hl
+    push hl
+    ld hl, [dasm_E9_str]
+    call print_str
+    pop hl
+    jp disassemble_continue
+dasm_E9_str:
+    db "JP (IY)",0x00
+
+
+dasm_00: ;JP nn (276)
+    inc hl
+    push hl
+    ld hl, [dasm_00_str]
+    call print_str
+    pop hl
+    jp disassemble_continue
+dasm_00_str:
+    db "NOP",0x00
+
+dasm_FF: ;JP nn (276)
+    inc hl
+    push hl
+    ld hl, [dasm_FF_str]
+    call print_str
+    pop hl
+    jp disassemble_continue
+dasm_FF_str:
+    db "---",0x00
+
+
+dasm_print16hex_addr:
+    ld a,"$"
+    call print_char
+    ld a,h 
+    call print_a_hex
+    ld a,l
+    call print_a_hex
+    ld a,"h"
+    call print_char
+    ld a," "
+    call print_char
+    ret
+
+dasm_print8hex:
+    call print_a_hex
+    ld a,"h"
+    call print_char
+    ld a," "
+    call print_char
+    ret
+
+dasm_print8relhex:
+    push af
+    and 0x80
+    jp nz, dasm_print8relhex_neg
+    ld a,"$"
+    call print_char
+    ld a,"+"
+    call print_char
+    pop af
+    call print_a_hex
+    ld a,"h"
+    call print_char
+    ret
+
+dasm_print8relhex_neg:
+    ld a,"$"
+    call print_char
+    ld a,"-"
+    call print_char
+    pop af
+    neg
+    call print_a_hex
+    ld a,"h"
+    call print_char
+    ret
+
+
+dasm_printFlags:
+    push hl
+    ld hl, [dasm_printFlags_table]
+    rlca
+    ld b,0
+    ld c,a
+    add hl,bc
+    call print_str
+    ld a, " "
+    call print_char
+    pop hl
+    ret
+
+dasm_printFlags_table:
+    db "NZ",0
+    db "Z",0,0
+    db "NC"
+    db "C",0,0
+    db "PO",0
+    db "PE",0
+    db "P",0,0
+    db "M",0,0

OperatingSystem/monitor_v2/include/.old/parity.s

@@ -0,0 +1,16 @@
+; a contains data
+; bc destroied
+; carry is set if odd, reset if even
+calc_parity:
+    ld c,0  ;parity data
+    ld b,8  ;bit counter
+calc_parity_loop:
+    rrca
+    jr nc,calc_parity_loop_2    ;if not zero then skip increment
+    inc c
+calc_parity_loop_2:
+    djnz calc_parity_loop
+    ld a,c
+    rra     ;carry is set to bit 0 of high-counter. 
+            ;if bit1 is set -> odd # of 1s else even # of 1s
+    ret