	org 32768
.core.__START_PROGRAM:
	di
	push ix
	push iy
	exx
	push hl
	exx
	ld (.core.__CALL_BACK__), sp
	ei
	call .core.__MEM_INIT
	jp .core.__MAIN_PROGRAM__
.core.__CALL_BACK__:
	DEFW 0
.core.ZXBASIC_USER_DATA:
	; Defines HEAP SIZE
.core.ZXBASIC_HEAP_SIZE EQU 4768
.core.ZXBASIC_MEM_HEAP:
	DEFS 4768
	; Defines USER DATA Length in bytes
.core.ZXBASIC_USER_DATA_LEN EQU .core.ZXBASIC_USER_DATA_END - .core.ZXBASIC_USER_DATA
	.core.__LABEL__.ZXBASIC_USER_DATA_LEN EQU .core.ZXBASIC_USER_DATA_LEN
	.core.__LABEL__.ZXBASIC_USER_DATA EQU .core.ZXBASIC_USER_DATA
_a:
	DEFB 00, 00
.core.ZXBASIC_USER_DATA_END:
.core.__MAIN_PROGRAM__:
	ld hl, .LABEL.__LABEL0
	xor a
	call .core.USR_STR
	ld (_a), hl
	ld hl, 0
	ld b, h
	ld c, l
.core.__END_PROGRAM:
	di
	ld hl, (.core.__CALL_BACK__)
	ld sp, hl
	exx
	pop hl
	exx
	pop iy
	pop ix
	ei
	ret
.LABEL.__LABEL0:
	DEFW 0001h
	DEFB 41h
	;; --- end of user code ---
#line 1 "/zxbasic/src/lib/arch/zx48k/runtime/usr_str.asm"
	; This function just returns the address of the UDG of the given str.
	; If the str is EMPTY or not a letter, 0 is returned and ERR_NR set
; to "A: Invalid Argument"
	; On entry HL points to the string
	; and A register is non-zero if the string must be freed (TMP string)
#line 1 "/zxbasic/src/lib/arch/zx48k/runtime/error.asm"
	; Simple error control routines
; vim:ts=4:et:
	    push namespace core
	ERR_NR    EQU    23610    ; Error code system variable
	; Error code definitions (as in ZX spectrum manual)
; Set error code with:
	;    ld a, ERROR_CODE
	;    ld (ERR_NR), a
	ERROR_Ok                EQU    -1
	ERROR_SubscriptWrong    EQU     2
	ERROR_OutOfMemory       EQU     3
	ERROR_OutOfScreen       EQU     4
	ERROR_NumberTooBig      EQU     5
	ERROR_InvalidArg        EQU     9
	ERROR_IntOutOfRange     EQU    10
	ERROR_NonsenseInBasic   EQU    11
	ERROR_InvalidFileName   EQU    14
	ERROR_InvalidColour     EQU    19
	ERROR_BreakIntoProgram  EQU    20
	ERROR_TapeLoadingErr    EQU    26
	; Raises error using RST #8
__ERROR:
	    ld (__ERROR_CODE), a
	    rst 8
__ERROR_CODE:
	    nop
	    ret
	; Sets the error system variable, but keeps running.
	; Usually this instruction if followed by the END intermediate instruction.
__STOP:
	    ld (ERR_NR), a
	    ret
	    pop namespace
#line 9 "/zxbasic/src/lib/arch/zx48k/runtime/usr_str.asm"
#line 1 "/zxbasic/src/lib/arch/zx48k/runtime/sysvars.asm"
	;; -----------------------------------------------------------------------
	;; ZX Basic System Vars
	;; Some of them will be mapped over Sinclair ROM ones for compatibility
	;; -----------------------------------------------------------------------
	push namespace core
SCREEN_ADDR:        DW 16384  ; Screen address (can be pointed to other place to use a screen buffer)
SCREEN_ATTR_ADDR:   DW 22528  ; Screen attribute address (ditto.)
	; These are mapped onto ZX Spectrum ROM VARS
	CHARS               EQU 23606  ; Pointer to ROM/RAM Charset
	TV_FLAG             EQU 23612  ; Flags for controlling output to screen
	UDG                 EQU 23675  ; Pointer to UDG Charset
	COORDS              EQU 23677  ; Last PLOT coordinates
	FLAGS2              EQU 23681  ;
	ECHO_E              EQU 23682  ;
	DFCC                EQU 23684  ; Next screen addr for PRINT
	DFCCL               EQU 23686  ; Next screen attr for PRINT
	S_POSN              EQU 23688
	ATTR_P              EQU 23693  ; Current Permanent ATTRS set with INK, PAPER, etc commands
	ATTR_T              EQU 23695  ; temporary ATTRIBUTES
	P_FLAG              EQU 23697  ;
	MEM0                EQU 23698  ; Temporary memory buffer used by ROM chars
	SCR_COLS            EQU 33     ; Screen with in columns + 1
	SCR_ROWS            EQU 24     ; Screen height in rows
	SCR_SIZE            EQU (SCR_ROWS << 8) + SCR_COLS
	pop namespace
#line 10 "/zxbasic/src/lib/arch/zx48k/runtime/usr_str.asm"
#line 1 "/zxbasic/src/lib/arch/zx48k/runtime/free.asm"
; vim: ts=4:et:sw=4:
	; Copyleft (K) by Jose M. Rodriguez de la Rosa
	;  (a.k.a. Boriel)
;  http://www.boriel.com
	;
	; This ASM library is licensed under the BSD license
	; you can use it for any purpose (even for commercial
	; closed source programs).
	;
	; Please read the BSD license on the internet
	; ----- IMPLEMENTATION NOTES ------
	; The heap is implemented as a linked list of free blocks.
; Each free block contains this info:
	;
	; +----------------+ <-- HEAP START
	; | Size (2 bytes) |
	; |        0       | <-- Size = 0 => DUMMY HEADER BLOCK
	; +----------------+
	; | Next (2 bytes) |---+
	; +----------------+ <-+
	; | Size (2 bytes) |
	; +----------------+
	; | Next (2 bytes) |---+
	; +----------------+   |
	; | <free bytes...>|   | <-- If Size > 4, then this contains (size - 4) bytes
	; | (0 if Size = 4)|   |
	; +----------------+ <-+
	; | Size (2 bytes) |
	; +----------------+
	; | Next (2 bytes) |---+
	; +----------------+   |
	; | <free bytes...>|   |
	; | (0 if Size = 4)|   |
	; +----------------+   |
	;   <Allocated>        | <-- This zone is in use (Already allocated)
	; +----------------+ <-+
	; | Size (2 bytes) |
	; +----------------+
	; | Next (2 bytes) |---+
	; +----------------+   |
	; | <free bytes...>|   |
	; | (0 if Size = 4)|   |
	; +----------------+ <-+
	; | Next (2 bytes) |--> NULL => END OF LIST
	; |    0 = NULL    |
	; +----------------+
	; | <free bytes...>|
	; | (0 if Size = 4)|
	; +----------------+
	; When a block is FREED, the previous and next pointers are examined to see
	; if we can defragment the heap. If the block to be breed is just next to the
	; previous, or to the next (or both) they will be converted into a single
	; block (so defragmented).
	;   MEMORY MANAGER
	;
	; This library must be initialized calling __MEM_INIT with
	; HL = BLOCK Start & DE = Length.
	; An init directive is useful for initialization routines.
	; They will be added automatically if needed.
#line 1 "/zxbasic/src/lib/arch/zx48k/runtime/heapinit.asm"
; vim: ts=4:et:sw=4:
	; Copyleft (K) by Jose M. Rodriguez de la Rosa
	;  (a.k.a. Boriel)
;  http://www.boriel.com
	;
	; This ASM library is licensed under the BSD license
	; you can use it for any purpose (even for commercial
	; closed source programs).
	;
	; Please read the BSD license on the internet
	; ----- IMPLEMENTATION NOTES ------
	; The heap is implemented as a linked list of free blocks.
; Each free block contains this info:
	;
	; +----------------+ <-- HEAP START
	; | Size (2 bytes) |
	; |        0       | <-- Size = 0 => DUMMY HEADER BLOCK
	; +----------------+
	; | Next (2 bytes) |---+
	; +----------------+ <-+
	; | Size (2 bytes) |
	; +----------------+
	; | Next (2 bytes) |---+
	; +----------------+   |
	; | <free bytes...>|   | <-- If Size > 4, then this contains (size - 4) bytes
	; | (0 if Size = 4)|   |
	; +----------------+ <-+
	; | Size (2 bytes) |
	; +----------------+
	; | Next (2 bytes) |---+
	; +----------------+   |
	; | <free bytes...>|   |
	; | (0 if Size = 4)|   |
	; +----------------+   |
	;   <Allocated>        | <-- This zone is in use (Already allocated)
	; +----------------+ <-+
	; | Size (2 bytes) |
	; +----------------+
	; | Next (2 bytes) |---+
	; +----------------+   |
	; | <free bytes...>|   |
	; | (0 if Size = 4)|   |
	; +----------------+ <-+
	; | Next (2 bytes) |--> NULL => END OF LIST
	; |    0 = NULL    |
	; +----------------+
	; | <free bytes...>|
	; | (0 if Size = 4)|
	; +----------------+
	; When a block is FREED, the previous and next pointers are examined to see
	; if we can defragment the heap. If the block to be breed is just next to the
	; previous, or to the next (or both) they will be converted into a single
	; block (so defragmented).
	;   MEMORY MANAGER
	;
	; This library must be initialized calling __MEM_INIT with
	; HL = BLOCK Start & DE = Length.
	; An init directive is useful for initialization routines.
	; They will be added automatically if needed.
	; ---------------------------------------------------------------------
	;  __MEM_INIT must be called to initalize this library with the
	; standard parameters
	; ---------------------------------------------------------------------
	    push namespace core
__MEM_INIT: ; Initializes the library using (RAMTOP) as start, and
	    ld hl, ZXBASIC_MEM_HEAP  ; Change this with other address of heap start
	    ld de, ZXBASIC_HEAP_SIZE ; Change this with your size
	; ---------------------------------------------------------------------
	;  __MEM_INIT2 initalizes this library
; Parameters:
;   HL : Memory address of 1st byte of the memory heap
;   DE : Length in bytes of the Memory Heap
	; ---------------------------------------------------------------------
__MEM_INIT2:
	    ; HL as TOP
	    PROC
	    dec de
	    dec de
	    dec de
	    dec de        ; DE = length - 4; HL = start
	    ; This is done, because we require 4 bytes for the empty dummy-header block
	    xor a
	    ld (hl), a
	    inc hl
    ld (hl), a ; First "free" block is a header: size=0, Pointer=&(Block) + 4
	    inc hl
	    ld b, h
	    ld c, l
	    inc bc
	    inc bc      ; BC = starts of next block
	    ld (hl), c
	    inc hl
	    ld (hl), b
	    inc hl      ; Pointer to next block
	    ld (hl), e
	    inc hl
	    ld (hl), d
	    inc hl      ; Block size (should be length - 4 at start); This block contains all the available memory
	    ld (hl), a ; NULL (0000h) ; No more blocks (a list with a single block)
	    inc hl
	    ld (hl), a
	    ld a, 201
	    ld (__MEM_INIT), a; "Pokes" with a RET so ensure this routine is not called again
	    ret
	    ENDP
	    pop namespace
#line 69 "/zxbasic/src/lib/arch/zx48k/runtime/free.asm"
	; ---------------------------------------------------------------------
	; MEM_FREE
	;  Frees a block of memory
	;
; Parameters:
	;  HL = Pointer to the block to be freed. If HL is NULL (0) nothing
	;  is done
	; ---------------------------------------------------------------------
	    push namespace core
MEM_FREE:
__MEM_FREE: ; Frees the block pointed by HL
	    ; HL DE BC & AF modified
	    PROC
	    LOCAL __MEM_LOOP2
	    LOCAL __MEM_LINK_PREV
	    LOCAL __MEM_JOIN_TEST
	    LOCAL __MEM_BLOCK_JOIN
	    ld a, h
	    or l
	    ret z       ; Return if NULL pointer
	    dec hl
	    dec hl
	    ld b, h
	    ld c, l    ; BC = Block pointer
	    ld hl, ZXBASIC_MEM_HEAP  ; This label point to the heap start
__MEM_LOOP2:
	    inc hl
	    inc hl     ; Next block ptr
	    ld e, (hl)
	    inc hl
	    ld d, (hl) ; Block next ptr
	    ex de, hl  ; DE = &(block->next); HL = block->next
	    ld a, h    ; HL == NULL?
	    or l
	    jp z, __MEM_LINK_PREV; if so, link with previous
	    or a       ; Clear carry flag
	    sbc hl, bc ; Carry if BC > HL => This block if before
	    add hl, bc ; Restores HL, preserving Carry flag
	    jp c, __MEM_LOOP2 ; This block is before. Keep searching PASS the block
	;------ At this point current HL is PAST BC, so we must link (DE) with BC, and HL in BC->next
__MEM_LINK_PREV:    ; Link (DE) with BC, and BC->next with HL
	    ex de, hl
	    push hl
	    dec hl
	    ld (hl), c
	    inc hl
	    ld (hl), b ; (DE) <- BC
	    ld h, b    ; HL <- BC (Free block ptr)
	    ld l, c
	    inc hl     ; Skip block length (2 bytes)
	    inc hl
	    ld (hl), e ; Block->next = DE
	    inc hl
	    ld (hl), d
	    ; --- LINKED ; HL = &(BC->next) + 2
	    call __MEM_JOIN_TEST
	    pop hl
__MEM_JOIN_TEST:   ; Checks for fragmented contiguous blocks and joins them
	    ; hl = Ptr to current block + 2
	    ld d, (hl)
	    dec hl
	    ld e, (hl)
	    dec hl
	    ld b, (hl) ; Loads block length into BC
	    dec hl
	    ld c, (hl) ;
	    push hl    ; Saves it for later
	    add hl, bc ; Adds its length. If HL == DE now, it must be joined
	    or a
	    sbc hl, de ; If Z, then HL == DE => We must join
	    pop hl
	    ret nz
__MEM_BLOCK_JOIN:  ; Joins current block (pointed by HL) with next one (pointed by DE). HL->length already in BC
	    push hl    ; Saves it for later
	    ex de, hl
	    ld e, (hl) ; DE -> block->next->length
	    inc hl
	    ld d, (hl)
	    inc hl
	    ex de, hl  ; DE = &(block->next)
	    add hl, bc ; HL = Total Length
	    ld b, h
	    ld c, l    ; BC = Total Length
	    ex de, hl
	    ld e, (hl)
	    inc hl
	    ld d, (hl) ; DE = block->next
	    pop hl     ; Recovers Pointer to block
	    ld (hl), c
	    inc hl
	    ld (hl), b ; Length Saved
	    inc hl
	    ld (hl), e
	    inc hl
	    ld (hl), d ; Next saved
	    ret
	    ENDP
	    pop namespace
#line 11 "/zxbasic/src/lib/arch/zx48k/runtime/usr_str.asm"
	    push namespace core
USR_STR:
	    PROC
	    ex af, af'     ; Saves A flag
	    ld a, h
	    or l
	    jr z, USR_ERROR ; a$ = NULL => Invalid Arg
	    ld d, h         ; Saves HL in DE, for
	    ld e, l         ; later usage
	    ld c, (hl)
	    inc hl
	    ld a, (hl)
	    or c
	    jr z, USR_ERROR ; a$ = "" => Invalid Arg
	    inc hl
	    ld a, (hl) ; Only the 1st char is needed
	    and %11011111 ; Convert it to UPPER CASE
	    sub 144   ; CODE(UDG "A")
	    jr nc, CONT
	    add a, 144   ; It was a letter
	    sub 'A'
	    LOCAL CONT
CONT:
	    ld l, a
	    ld h, 0
	    add hl, hl
	    add hl, hl
	    add hl, hl	 ; hl = A * 8
	    ld bc, (UDG)
	    add hl, bc
	    ;; Now checks if the string must be released
	    ex af, af'  ; Recovers A flag
	    or a
	    ret z   ; return if not
	    push hl ; saves result since __MEM_FREE changes HL
	    ex de, hl   ; Recovers original HL value
	    call __MEM_FREE
	    pop hl
	    ret
USR_ERROR:
	    ex de, hl   ; Recovers original HL value
	    ex af, af'  ; Recovers A flag
	    or a
	    call nz, __MEM_FREE
	    ld a, ERROR_InvalidArg
	    ld (ERR_NR), a
	    ld hl, 0
	    ret
	    ENDP
	    pop namespace
#line 24 "arch/zx48k/usr0.bas"
	END
