[VG5000] struggling on converting binary files to k7

[nitrofurano]

hi,
as a next step on the VG5000 development, i started trying to code a binary to .k7 converter - it would embed a binary file into a .k7 image tape (i did a similar converter for zx-spectrum .tap file once) - for that converter, i used sdlBasic on Linux (later i'll recode it on Python)

http://pastebin.com/EBCM2aCg

the source and the result is in the attachment - and when i try to load the .k7 file with cload, it shows an error message "Ligne non définie" after "Trouvé:exampl"

maybe i needed to add a loader in Basic before, or enter "cload" in a different way? the idea would be about having that .bin file (compiled from Boriel's ZX-Basic Compiler) loaded and executed automatically, just like those good old games for VG5000 available in .k7 files as well

any ideas? thanks in advance!

[Markerror]

Hello Paulo,

Unfortunately, the VG5000 can't execute binary files (that's seems weird, but it's like that).

Philips commercial games files are a mix of a basic file (with just the CALL &"xxxx" command) and the binary code.

Markerror

[nitrofurano]

and how these .k7 files are saved, or, how the .k7 header (including a tokenized ‘CALL &"5000"’ (or whatever) somewhere ), that i could use as a template for having it automatically gererated from a script after getting compiled binaries from any cross-compiler, whatever Boriel's ZX-Basic Compiler, z88dk (a cross-c compiler), wla-dx (a cross-assembler), etc.

[Markerror]

Hi,

I spent a little time to create an example of a executable file for the VG5000. I think it may help you .

Markerror

; VG5000 header example
; T&J/GPA in july 2013 !

; Example of Z80 code launched automatically by a Basic CALL
; Same tchnic as the one used in commercial games from Philips
; Basic line is 10 CALL 18954 followed by asm code.

; Use WINAPE to create the K7 file, then load it in DCVG5K with
; classical CLOAD command. Press a key to clear the screen.
; No need to save HL and IX registers as the program does not
; return to Basic.

ORG &49D1
WRITE "TEST.K7"

length equ &3B ; length of the file (without header)
checksum equ &132F ; sum of datas between 'main' and 'file_footer'

; file header

db &D3,&D3,&D3,&D3,&D3,&D3,&D3,&D3,&D3,&D3,&4D,&56,&47,&35,&30,&30
db &30,&00
db &31,&30,&00,&00,&00 ; line 10 !
db &00,&00,&00,&FB,&49 ; &49FB = exec address of a Basic file
defw length
defw checksum
db &D6,&D6,&D6,&D6,&D6,&D6,&D6,&D6,&D6,&D6

; &49FB
; Basic file that calls binary code

db &00,&08,&4A,&0A,&00 ; line 10
db &9F,&31,&38,&39,&35,&34,&3A,&00 ; CALL 18954 / &4A0A
db &00,&00

; binary code
; &4A0A

main DI
LD HL,&4803
LD A,(color)
INC A
CP &8
JR NZ,main2
XOR A
main2
LD (color),A
LD C,A ; save bits 0 to 2

RLA ; rotation to set the color
RLA ; to bits 4 to 6
RLA
RLA
ADD A,C
OR &80 ; bit 7 on
LD (HL),A
CALL &9E ; should clear screen and fill it with new color

LD A,&1
LD (&47FB),A ; ask for screen refresh

EI
HALT


main1
CALL &32B7 ; scan key
AND A ; no key pressed ?
JR Z,main1
JR main

color db &00

; file_footer
db &00

[nitrofurano]

thanks!

[nitrofurano]

btw, based on your help, i tried what i'm sending in the attachment - tried to "cload", and it shows "Mauvais fichier"... - any clue? :S (thanks in advance again! )

[nitrofurano]

btw, perhaps the "mauvais fichier" error message appears because the checksum isn't considering the tokenized-basic bytes after the 0xD6 10 bytes sequence, and "main"? so i tried to add 576 to the checksum, and the error persists...

[Markerror]

Hi,

Gosh... You are right, the checksum must take datas from &49FB to file_footer, not main in my example...

I have fixed your test file example01.k7 and managed to load it correctly in memory.

Correct values for length and checksum are :

&15F
&9D27

When you encounter a checkum error, it display the message "Mauvais fichier"
If the length is wrong and the file too short comparing to the length value, it might just say "Trouvé <file>" then DcVG5K say that there is no more file on the K7 (not tested).

Markerror

[nitrofurano]

yes, works! thanks! \o/ - this is a very significant goal in the cross-compiling development, at least in my humble viewpoint!

[nitrofurano]

I spent a little time to create an example of a executable file for the VG5000. I think it may help you .
(...)

Markerror, here in the attachment is your assembly snippet as inline-assembly into Boriel's ZX-Basic Compiler, which seems to work fine! - btw, do you know where from can i test more VG5000 snippets in assembly that i could use for Boriel's ZX-Basic Compiler development improvement? thanks!