Hi there,

I can't for the life of me work out why I've hit this wall. I'm currently designing the graphics for my game, keeping character maps in one file and test harness in another. It crashes out with "J Invalid I/O device, 30:1".

The code in the character file, called, _graphics.bas is as follows:

Hi

I have been looking into the ZX0 library

Having created a compress file by running this "zx0 testscreen.scr"
And to us this file this is a test file I created t.bas

#include "zx0.bas"

10 dzx0Standard(@testscreen1, 16384)
20 GOTO 20

testscreen1:
    asm
        incbin "testscreen.scr.zx0"
    end asm

When compiled and run it indeed does display the image on screen.
Some questions:-

Q1.I have been able to convert some artwork (PNG) to .SCR and compress this and then load it on screen BUT (newbie alert) I am running out of memory/program crashes/resets Emulator.
So the question is, can I do this and if so HOW?
(A) load from a M: drive (emulator allowing) and/or
(B) use the 128K Mode and then use the memory banks for images and leave the '48K' for the main game?

Q2. How can I display the SCR file but only print it to the top half of the screen?
1/3 or 2/3rds is okay as well? Is there any code examples (ASM/ZXB)

Q3. Next to the text,
I want to next compress text files that contain a description of a game room.
Looking at an example I tried this (don't laugh!) :-

dzx0Standard(@Text1, 50000)

Text1:
asm
incbin "location1.txt.zx00"
end asm
Text2:
asm
incbin "location2.txt.zx00"
end asm

But this does nothing but load it to the address of 50000 but I want the routine to return a STRING containing the decompressed text?

Quote:UPDATE 4th April 2021: I have worked how to do Q3 in a standalone test.bas file but when I do this in my main program it crashes the app soon after starting it up?
I am using these params --tzx --BASIC --autorun  --heap=1000 --optimize 2  --org=25000--debug-memory  --debug-array 

Hi,
Recently started experimented with the compiler. It's been great so far but I've just started getting unexpected errors using arrays. Compiling the snippet below results in:
test.bas:55: error: Undefined GLOBAL label '._myArray'.  
I can't see why this is failing ?  Am I doing something stupid ?  
I've used 1.14.1 and the latest state of the repo. Is it a bug ?

DIM myArray(1 to 6) as ubyte

SUB Init(byval num as ubyte)
    DIM i as ubyte
    FOR i=1 TO num
        myArray(i) = 0
    NEXT i
END SUB

Init(6)


Jonathan

Hi everyone (probably for the attention of Boriel),

My search for the source of instability in my game continues, though I no longer think it is to do with memory management, but a possible bug in the compiler, for the implementation of LOAD "..." CODE. I have noticed that part of my program gets corrupted after I use LOAD "..." CODE to load some UDGs at the top of memory. Digging in to the implementation of the function, I found the following code (sorry, I can't copy and paste code out of the emulator I am using):

https://1drv.ms/u/s!Atca6hVb5b8Tp5JxCEWC...g?e=qGHdEg

At the end of the snippet, a call is made to 0xE6E1, which is a wrapper to the ROM loader routine (in this case, to load a tape header). IX points to the place in memory where the header should be loaded, which -- in this case -- is inside my program code. If I understand correctly what is going on, the snippet starts with a call to MEM_FREE (0xDB56, in this case) which returns a pointer to space in the heap (perhaps where the header can be stored?). However, the IX register is loaded with 2*SP and passed to the tape loader, which I think is a mistake.

Is that a possible bug?

I wonder if there is a way to print the available memory your compile ZX Basic program has used whilst running it?

One more question on memory usage, which would be better in terms of reducing memory overhead?

1) IF WORD$ = "SAVE WORLD" THEN


or
2) IF WORD = 99 and WORD=98 THEN

thanks in advance
Ken

Hi everyone,



I am seeing some strange memory problems when compiling a reasonably large program, which probably means I don't understand how the compiler organises memory.




Specifically, I have a program that is around 28kb in size, including a 1kb heap. Depending on the origin value I use, the program will either work or crash, but not as you might expect.




Initially, I set the origin of the code to 26000 (that is, "--org 26000") and this worked fine for a time. However, when my program reached a certain length (from memory, around 25kb), I started to see odd behaviour (corrupted strings and Out Of Memory errors). I tried increasing the heap size (to 2kb, 3kb, 4kb, 5kb, 6kb), though this didn't help. I then tried changing the origin to 28000 and then everything was fine again.




A little later on, with some more code added, I started to see problems again, so I again tried increasing the origin address--now to 29000 and again all is fine.




I'm confused because:

1. the program isn't that big, fitting in between address 29000 and 57,353 (right now), so well clear of user-defined graphics and any Sinclair BASIC workspaces
   
2. I would have expected that lowering the origin address would be more likely to help, if there was a lack of memory, rather than increasing it.
   

Hi everyone,

I'd like to use --explicit to force me to define all variables before using them, to reduce the risk of bugs. However, I see an issue because my program uses the Print42 library and it contains a definition that seems to violate the --explicit option.

Specifically, if you try to compile a program that includes Print42 library, using --explicit, you will see an error something like:

Hi everyone,

In ZXBASIC, is this a valid program?

Hello Boriel,

The following array initiation code I don't think is initiating the array data at the correct address. In the example below, the peek returns a value of 255 rather than 1, also @test doesn't return a value of $c000  (Version  1.15.0-beta4 + NextBuild)

Hi everyone,

I would like to use the --debug-array option to check I have not used out-of-range array indices in my program. However, it appears that I need to give the compiler more information, to use the option in a program that passes arrays as function arguments.

For example, the following simple program appears to compile/ run correctly: