Boriel Basic Forum - Help & Support

location of heap management code...

Tue, 24 Feb 2026 13:17:50 +0000

I'd like to use strings and arrays in my paged code, but I seem to have reached a blockage whereby, even though my paged-code looks like:

Code:
#PRAGMA push(case_insensitive)

#PRAGMA case_insensitive = True

#define STANDALONE  ' remove ROM initialization and SysVars...

Asm

    org $6000

    di

End Asm

s_stage_init()

Asm

    ret

End Asm

#include "constants.bas"

#include "globals.bas"

#include "stage-include.bas"

Sub s_init_keyboard_table_ZX_keys()

    ' effect: populates the lookup table for the 40-key spectrum matrix

    ' row 0: port $FEFE

    gub_zxkeys(0)  = 0   ' caps shift

'...

    gub_zxkeys(55) = 127 ' delete (standard)

End Sub

Sub s_init_keyboard_table_ZX_symkeys()

    ' row 0: z, x, c, v

    gub_zxsymkeys(1)  = 58  ' :

'...

    gub_zxsymkeys(55) = 127 ' delete (standard)

End Sub

Sub s_init_title_screen()

    ' footer prompt

    s_print_string_at( 28, 21, "Press any key to begin..."  , UB_BRIGHT_YELLOW )

    ' wait for player input

    s_get_key()

    ' check if the one-hour timeout occurred

    If guw_key_code = 0 Then gub_core_end = true

End Sub

Sub s_stage_init()

    s_init_keyboard_table_ZX_keys()

    s_init_keyboard_table_ZX_symkeys()

    s_init_title_screen()

End Sub

and when I compile with :

Code:
python $Compiler "$($Name).bas" -f bin -o "$($Name).bin" --org 24576 -W150 --headerless --explicit --strict --zxnext -i --arch zxnext --opt-strategy size --heap-address 32000 --heap-size 767 -M "$($Name).map"

then I still seem to end up with some kind of header code that makes a call to $46A4...

Code:
>6001  CALL 46A4        PC  6001

 6004  NOP              SP  FFFA

 6005  NOP              AF  FFFF'3C40

 6006  NOP              SZ5H3PNC

 6007  NOP              HL  0001'3C44

 6008  NOP              DE  0000'FFFF

 6009  NOP              BC  0000'5393

 600A  LD BC, 6013      IX  FFF1

 600D  EX AF, AF'       IY  EFF3

 600E  LD B, A          IR  001B

 600F  NOP              IM1 IFF--

 6010  NOP              (HL) F3 00

 6011  NOP              (DE) 00 F3

                        (BC) 00 F3

(SP) 0C3C 010B 0000 F300 C300 0

which I think must be some kind of heap management setup...

...so please may I ask...

Is there a compiler switch or directive whereby I can get the heap management code tacked on just after my code ends, so that I can have private heap management per 8KB segment of paged code ?

Thank you.

non-paged supervisor code calling paged application code

Sun, 15 Feb 2026 15:01:23 +0000

Firstly, a proper thankyou to Boriel for the compiler. And secondly, also a proper thankyou to Duefectu for the beginner's guide book (I bought a hard copy), which I have read cover to cover (but I did skip the sound/audio sections ). And I bought a hard copy of Simon G's NextTech book too, again I have read it cover to cover (but skipped the sound/audio parts).

Using Boriel ZXBasic and as little Z80 machine code as I can get away with (until I need to performance tune)... my project is that I am trying to write a quasi "character cell" based application, like being on an old VT100, whereby the application uses all 64KB of the Z80 for itself, and thus no ZX Spectrum ROM, and which internally leverages a poor man's virtual memory framework, whereby I have a supervisor layer of non-paged code running in MMU0/1, which boots from $0000 and jumps over IM1 at $0038 to begin my main code properly at say $0050 where the application begins properly... and so I have my core non-paged system variables mapped in MMU2 and then I have my paged code to run from MMU3 - and then various different aspects of paged application data paging in and out MMU4/5/6, with finally MMU7 again being static non-paged to host the 5KB of screen tile map for an 80x32 screen, with the final 3KB of MMU7 being available for the stack pointer from $FFFE downwards.
phew...
I know my code will never work first time, I get that... but I feel fairly sure that I have the basic (excuse the pun) initial structure of what I want to achieve, with all of my system variables (so far identified) defined at static addresses in MMU2, and my main supervisor MMU paging and also my screen updating routines and keyboard reading routines written (to be permanently resident in MMU0/1) and the first of my paged blocks of code to run from MMU3, and I have gotten the source code clean enough pass through zxbc without the compiler spitting any hard errors... (just lots and lots of warnings)... but I've now hit a roadblock...

I get how I can have many separate pages of 8KB deposited across the ZX Next vast 200+ pages of 8KB across 1.75 MB of RAM, and I get how I can have my code paged in at MMU3 for my application to execute from $6000, and I can get my non-paged supervisor layer code to make calls such as uw_dummy = USR $6000 to call my paged code in MMU3, and thus wait for a return... but what I don't understand is how I can have many different paged code blocks where each is aware of *ALL* of the available core supervisor routines and their parameter structures and thus able to makes calls back in to the supervisor to run any of the many core system routines...

i.e. how can I make zxbc firstly compile the application core without dropping routines that zxbc thinks are unused, and yet also somehow get the compilations of many different "paged" application code to be aware of the core supervisor routines and their parameters and any return value data types (of functions).

e.g. I get this from my compilation of my "core.bas":
core.bas:115: warning: [W170] Function 's_crash' is never called and has been ignored
core.bas:154: warning: [W170] Function 's_fc_ram_copy' is never called and has been ignored
core.bas:165: warning: [W170] Function 's_clear_screen' is never called and has been ignored
core.bas:126: warning: [W170] Function 's_print_char_at' is never called and has been ignored
core.bas:143: warning: [W170] Function 's_print_string_at' is never called and has been ignored
core.bas:217: warning: [W170] Function 's_display_monitor' is never called and has been ignored
core.bas:283: warning: [W170] Function 'fub_key_get_minutes' is never called and has been ignored

...and I get this for my first stage of my application:
stage-include.bas:37: warning: [W170] Function 's_next_reg' is never called and has been ignored
stage-include.bas:38: warning: [W170] Function 's_return_to_zxos' is never called and has been ignored
stage-include.bas:39: warning: [W170] Function 's_crash' is never called and has been ignored
stage-include.bas:40: warning: [W170] Function 's_fc_ram_copy' is never called and has been ignored
stage-include.bas:42: warning: [W170] Function 's_clear_screen' is never called and has been ignored
stage-include.bas:43: warning: [W170] Function 's_print_char_at' is never called and has been ignored
stage-include.bas:44: warning: [W170] Function 's_print_string_at' is never called and has been ignored
stage-include.bas:45: warning: [W170] Function 's_display_monitor' is never called and has been ignored
stage-include.bas:47: warning: [W170] Function 'fub_key_get_minutes' is never called and has been ignored
stage-include.bas:48: warning: [W170] Function 's_key_wait_for_vblank' is never called and has been ignored
stage-include.bas:49: warning: [W170] Function 's_get_key' is never called and has been ignored
...
stage-init.bas:8: warning: [W170] Function 's_stage_init' is never called and has been ignored
stage-init.bas:20: warning: [W170] Function 's_init_keyboard_table_ZX_keys' is never called and has been ignored
stage-init.bas:21: warning: [W170] Function 's_init_keyboard_table_ZX_symkeys' is never called and has been ignored
stage-init.bas:18: warning: [W170] Function 's_init_load_palette' is never called and has been ignored
stage-init.bas:186: warning: [W170] Function 's_init_load_palette_entry' is never called and has been ignored
stage-init.bas:223: warning: [W170] Function 's_init_clear_screen' is never called and has been ignored
stage-init.bas:26: warning: [W170] Function 's_init_title_screen' is never called and has been ignored

...where stage-include.bas was my attempt to make each "stage" aware of a jump-table of locations of core routines:
Asm
; fixed jump table addresses for the linker
_s_main equ $0050
_s_next_reg equ $0053
_s_return_to_zxos equ $0056
_s_crash equ $0059
_s_fc_ram_copy equ $005C
_s_clear_screen equ $005F
_s_print_char_at equ $0062
_s_print_string_at equ $0065
_s_display_monitor equ $0068
_fub_key_get_minutes equ $006B
_s_key_wait_for_vblank equ $006E
_s_get_key equ $0071
End Asm

' implementation blocks to stop "not implemented" errors
' these contain no code; the equate above handles the address
Sub s_main(): End Sub
Sub s_next_reg(reg As UByte, value As UByte): End Sub
Sub s_return_to_zxos(): End Sub
Sub s_crash(error_code As UByte, error_text As String): End Sub
Sub Fastcall s_fc_ram_copy(src_address As UInteger, dest_address As UInteger, byte_count As UInteger): End Sub
Sub s_clear_screen(): End Sub
Sub s_print_char_at(x As UByte, y As UByte, char As UByte, colour As UByte): End Sub
Sub s_print_string_at(x As UByte, y As UByte, text As String, colour As UByte): End Sub
Sub s_display_monitor(): End Sub
Function fub_key_get_minutes() As UByte: return 0: End Function
Sub s_key_wait_for_vblank(): End Sub
Sub s_get_key(): End Sub

But clearly there is something I'm not getting, and I've reached the limits of capability of AI helper tools.

I had rationalised to myself that my build script should only call to zxbc to produce "-f asm" ASM files... as I expect to have to then somehow "link" the static core ASM and the many paged stage ASM together at some point... and I also seem to have rationalised that I may perhaps need to use sjasmplus to assemble my ".nex" package.

Does the above sound achievable? Or am I asking too much of the "Next" as a platform? i.e. is the "Next" only any good for paging graphics data, and no good for paging application code?

Old zxbasic game errors

Mon, 03 Nov 2025 20:32:31 +0000

trying Escape From Cnossus from 2013 getting this error

Error: 'subdivideHigh' is neither an array nor a function.

the line is

wall1 = subdivideHigh(x1, y1, x - 1, y2)

any help please

Error: Undefined GLOBAL label

Sun, 02 Nov 2025 12:43:21 +0000

Looking over an old file of mine that once worked I'm now getting Error: Undefined GLOBAL label . each one is going to a fastcall.

ie

ld hl, lineMSG
ld bc, end1-lineMSG
call myPrint42

calling

SUB fastcall myPrint42()
ASM
myPrint42:
push af
push ix
push hl
ld ix, PRINT42
CALL IXCALL
pop hl
pop ix
pop af
ret
END ASM
END SUB

gives me Error: Undefined GLOBAL label ".myPrint42"

any help please....

3DOS Commands?

Sun, 05 Oct 2025 21:33:54 +0000

Hi

I'm looking at using some 3DOS commands, starting to see how I can cat a disk.

I've takend the below code from the +3 manula (pg 200 to 203) which should allow me to get the CAT into memory - the code looks to activate the disk (and for example if I don't attach a disk, it give me abort/retry) but then "reboots"/crashes the emulator back to the +3 menu.

I'm assuming that there might be some incompatibility somewhere between, starting reading, and returning contorl to the program. Code is below.

Any thoughts?

(PS If the ASM didn't crash, the program wouldn't actually do anything anyway yet, as I've not sorted any output, or any caribles)

Code:
#include 

#include 

#INCLUDE  

PRINT "This is the start"

main()

SUB main()

    LET YesNo = "n"

    PRINT "do you want to CAT disk"

    YesNo = INPUT(1)

    IF YesNo="y" then

        Catalogue()

    END IF

    PRINT "Ed#nd Main"

END SUB

SUB Catalogue()

    ASM

        PUSH IX ; dos catalog corrupts ix

        PROC

        LOCAL   MYSTACK

        LOCAL   STACKSTORAGE

        LOCAL   BANKM

        LOCAL   PORT1

        LOCAL   CATBUFF

        LOCAL   DOS_CATALOG

        MYSTACK         EQU     9fffh ; 

        STACKSTORAGE    EQU     9000h ; save pointer

        BANKM           EQU     5b5ch ; system var that holds last value output to 7ff0h

        PORT1           EQU     7ffdh ; address of rom/ram switching port

        CATBUFF         EQU     8000h ; location for dos to output

        DOS_CATALOG     EQU     011Eh ; DOS routine to call

        JP start

        stardstar:  defb "*.*",255                    

        dosret:     defw 0

        start:

            DI

            LD (STACKSTORAGE),SP

            LD BC,PORT1         ; 

            LD A,(BANKM)        ; current switch state

            RES 4,A             ; move right to left in horizontal rom switch (3 to 2)

            OR 7                ; switch in ram page 7

            LD (BANKM),A        ; keep system var up to date

            OUT (C),A           ; switch ram and rom

            LD SP,MYSTACK       ; make sure stack is above 4000h and below bfeoh

            EI                  ; enable interrupts

            ; 

            LD HL,CATBUFF

            LD DE,CATBUFF+1

            LD BC,1024

            LD (HL),0

            LDIR

            LD B,64

            LD C,1

            LD DE, CATBUFF

            LD HL,stardstar             ;file name *.*

            CALL DOS_CATALOG            ;call dos catalog

            PUSH AF

            POP HL

            LD (dosret),HL              ; put here so can be seen from basic

            LD C,B                      ; number of files in catalog, low byte of bc

            LD B,0                      ; returned to basic by usr functio

            DI

            PUSH BC

            LD BC, PORT1

            LD A, (BANKM)

            SET 4, A                    ; move left to right (riom 2 to 3)

            AND 48h                     ; ram page 9

            LD (BANKM),A                ; update syste value

            OUT (C),A                   ;switch

            POP BC                      ; get back saved number of files

            LD SP,(STACKSTORAGE)        ; 

            EI

            ;RET ; not sure if thisis needed

        ENDP

        POP IX

        ;RET ; Not sure if this is needed here

    END ASM

END SUB

Printing with FZX

Mon, 14 Jul 2025 15:45:43 +0000

Hi, I'm new, so these are probably stupid questions. But, I'm confused about printing with printFzxStr. Is there any way to to get it to word wrap neatly? It's breaking to a new line in the middle of a word (or even the middle of a letter)

As a last resort, I guess I could have a go at writing my own word-wrap routine if I knew where to find the different widths of all the characters and the position of the text-printing cursor along the row. How would I go about finding them?

One final question. Is there a way to make FZX scroll when it reaches the bottom of the screen instead of just stopping ZX81-style with an error message?

Thanks

.tap file code not executed

Thu, 24 Apr 2025 16:09:58 +0000

Hello, I'm a newbie tinkering with the Spectrum.
I tried to get some code to test like the classic 'clock.bas' or 'circle. bas' and then converting a .bas file to .tap.
In some cases, I obtain some errors like:

manuelzompetta@Manuels-MacBook-Pro zxbasic % python zxbc.py clock.bas
clock.bas:21: warning: [W100] Using default implicit type 'float' for 'a'
clock.bas:22: warning: [W100] Using default implicit type 'float' for 'sx'
clock.bas:22: warning: [W100] Using default implicit type 'float' for 'sy'
clock.bas:25: warning: [W100] Using default implicit type 'ulong' for 't2'
Traceback (most recent call last):
File "/Users/manuelzompetta/Downloads/zxbasic/zxbc.py", line 12, in
sys.exit(zxbc.main()) # Exit
^^^^^^^^^^^
File "/Users/manuelzompetta/Downloads/zxbasic/src/zxbc/zxbc.py", line 155, in main
asm_output = backend.emit(optimize=OPTIONS.optimization_level > 0)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/Users/manuelzompetta/Downloads/zxbasic/src/arch/z80/backend/main.py", line 770, in emit
self._output_join(output, self._QUAD_TABLE[quad.instr].func(quad), optimize=optimize)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/Users/manuelzompetta/Downloads/zxbasic/src/arch/z80/backend/generic.py", line 362, in _cast
output.extend(to_long(tA))
^^^^^^^^^^^
File "/Users/manuelzompetta/Downloads/zxbasic/src/arch/z80/backend/common.py", line 401, in to_long
raise NotImplementedError(f"type conversion from {stype} to long is undefined")
NotImplementedError: type conversion from u32 to long is undefined

In other cases I obtain .tap file but when I execute it in the Spectrum or in an emulator nothing happens, I just obtain the welcome screen.

What I'm doing wrong?

Thanks

Creating +3 Menus - Loading external BAS files

Sat, 12 Apr 2025 05:18:24 +0000

Hello,

I'm creating Menus for my +3 game compilations but I can't find a way to load external BAS files.

With the LOAD command I can load only CODE & SCREEN$ files. There is a way to LOAD another BAS file included in the disks?

Like on standard +3 BASIC.

ie: LOAD "MYBASPRG" or LOAD "MYBASPRG.BAS"

Thanks in advance.

Example:

Randomize not very random?

Sun, 06 Apr 2025 12:21:25 +0000

I don't know if this should be in the bug section or is just a general question. There was an older question in the bug forum saying it would be fixed.

Making a card game, I use an array (0 to 51) for card numbers, then have a routine to shuffle it up.
With RANDOMIZE at top of program so it only gets used once each time the game is loaded, I consistently start with 2,0,3,48,9.
Moving it into the "new game" loop so it is run at the start of each new game, I'm always seeing 49,0,21,24.
I'm seeing the same sequence whether I use my Linux or Windows pc.
Not sure if it's something to do with FUSE emulator rather than ZX BASIC, and not using the FRAME setting which the help page mentions?
I've added my source as a txt file for reference.

hilo3.txt (Size: 4.05 KB / Downloads: 846)

Filling drawings

Fri, 07 Feb 2025 12:16:48 +0000

There's no function or command "fill", allowing to pass two coordinates and making the computer to fill all delimited pixels with the current color.

Code:
circle 50, 50, 30

fill 50, 50

In the eighties, I used to fill a circle with a for loop:

Code:
circle 50, 50, 30

for i = 1 to 30

    circle 50, 50, i

next i

I suppose I could do something like this for rectangles, as well. This is, however, slow, ugly (certain pixels remain unplotted), and clumsy. Is there an alternate way?
Thanks,

Headerless load routine in ZX Basic

Tue, 04 Feb 2025 05:19:37 +0000

Hello,
I'm trying to code a simple headerless LOAD routine in ZX Basic using the inline assembly feature of the compiler. The basic idea here is to write a function that uses assembly to set up the necessary registers and call the ROM routine 0556h for a headerless load (e.g. to load an extra level from the tape). I have some progress in this area, but it looks like I misunderstand how to clean up things correctly after the ROM routine returns and my function ends, so the poor Speccy either hangs or is reset after the code loading routine completes. I tried a few things so far, but the experiment that went the farthest so far is this one:

Code:
function hload(addr as uInteger, size as uInteger) as uByte

    asm

        pop hl

        pop de

        pop ix

        ld a, 255

        scf

        call 0556h

        push hl

    end asm

end function

The expected result is that calling this function, for instance, in this way:

Code:
hload(16384, 6912)

should be able to load standard ZX screen data correctly. Trying to load a screen this way indicates that the screen is indeed loaded into the right area of memory, but once the loading completes, the computer is reset.

I'm pretty sure that this indicates that something is screwed up at the end of the function call. Could be due to the fact that SP or something else is modified from within 0556h and that changes the register state, or something else along those lines, but I can't quite figure it out :/ I would appreciate some help since I'm not sure how to proceed. I tried a few other cleanup tricks, but none of them worked.

Another question is: how do I properly return a value from this function? As far as I understand, the return value can be stored in the A register. Suppose I wanted to indicate that the tape loaded correctly with a value of 0, would I simply LD A, 0 at the end of the function and that would be enough? This, of course, is a separate issue once I can actually get this function to load anything without resetting the PC or hanging

Thanks in advance.

Turn Off Keyword Hint

Thu, 30 Jan 2025 12:00:52 +0000

Is it possible to turn off the Keyword hints in ZXBasicStudio ?

I can't see them in the dropdown popup, and it annoyingly makes entering code awkward.

Unable to see Key Words

Wed, 29 Jan 2025 11:57:37 +0000

I had an issue with my Boriel that prevented me from using the debugger. This has been fixed with help from the forum and me installing the latest version of the Boriel ZXBasicStudio.

My issue now is that I can no longer see Key Words when entering code (see attachment). If anyone could help on this it would be highly appreciated.

I checked with the older version and that does show the KeyWords, but won't run in debug mode.

key words.jpg (Size: 57.19 KB / Downloads: 548)

Just Installed ZXBasicStudio but cannot debug

Tue, 28 Jan 2025 17:20:13 +0000

Hi, I am new to the forum, but not to the ZX Spectrum :-)

I have installed the latest version of ZXBasicStudio and ZXBasic compiler onto my PC.

I have created a very simple program than runs from within ZXBasicStudio.

However, when I try and Debug it creates some new files in the project folder:

Main.buildtemp.bas
Main.buildtemp.bin
Main.buildtemp.ir
MEMORY_MAP

but I get the following error mesage:

Exception: Could not find file 'D:\BorielDev\Projects\HelloWorld\Main.buildtemp.ic' at

.
.
.

Screenshot below...

If anyone could point me to where I am going wrong it would be highly appreciated.

John

ZXBasicIssue.jpg (Size: 261.7 KB / Downloads: 620)

Question on file extension

Sat, 18 Jan 2025 22:11:10 +0000

I am working my way through the book 'Boriel Basic for Beginners'. It is a very good book and well written. I have convinced my friend to buy a copy too.

On page 166 in the example the first command is '#INCLUDE "ship.gdu.bas". When I exported the UDG's as per the instructions on page 165 it creates a file 'ship.gdu.zxbas'

I was wondering why it did not export with the extension '.bas'. I understand I just need to change the extension in the code and it loads in fine, I just want to understand why. It may be something I have done wrong.

ZeDeX82