Disk access for Compiler256

[senior_falcon]

I have been looking at the possibility of implementing disk access for the XB compiler. I now have the compiler handling the open, close, input and linput, and print to some extent, but there still is a ways to go before that is fully implemented. That's the easy part...The hard part is writing the runtime routines for disk access, and I have neither time nor interest in doing that. If someone is interested in tackling this I can provide information on how to interface with the compiled code - such things as how to pass numbers, strings, commonly used subroutines, workspaces, etc.

[RXB]

I would suggest using the Miller Graphics GPL LINK DSR for full access to all types of devices. (Even Cassette or Hex Tape.)

[+Lee Stewart]

The MG GPLLNK/DSRLNK takes 174 bytes of ALC plus DSRLNK workspace of 32 bytes. I presume we're talking about maintaining the XB/TIB linked list of PABs for open files in graphics mode. It would be dicier if we have to also do it for bitmap mode because the space for PABs is limited in that mode.

 

...lee

[RXB]

I thought the idea was to maintain compatibility, but if that is not the goal then cross compiling is not the goal.

[senior_falcon]

MG GPLLNK is part of the compiler runtime, and I would just put the rest (DSRLNK) of it back in. Bitmap graphics are not a problem because they are not part of XB256. Most of the VDP is available; certainly as much as would be available to XB.

[Bones-69]

* Watching in excitement.

[senior_falcon]

Peripheral access for the compiler has been worked out in a limited way: only one file open at a time and DV only. I need to do some thorough testing over the next couple of days to see what has been overlooked, then will post.

[Opry99er]

[JamesD]

:)

What he said

[senior_falcon]

Looks like the programming is pretty much worked out. Limited to Display Variable files, any length you want. 3 files can be open at a time if needed. EOF and error handling are worked out so they work like in XB. I need to come up with a rigorous test to be sure:

1 - the files created by a compiled program are compatible with those created by an XB program.

2 - files created by XB can be read by a compiled program.

3 - the error handling works as expected.

4 - documentation needs to be updated

Been very busy but hope to get to this soon.

[Shift838]

This sounds very interesting.

[senior_falcon]

Updated compiler with disk access is posted in XB Game Developer's Package, post #1.