Custom kickstart

[iliak]

Hi,

Does anyone ever tried to make a custom kickstart to replace orignal Amiga's ROM to use within WinUAE ? Any source code, toolchain, linker options ?

Thanks !

[pandy71]

Search EAB for "remus" "kickstart"

for example http://www.mfilos.com/2010/12/guide-...kickstart.html

[iliak]

Hi pandy71

I'm sorry, I misspoke. I'm looking for how to build from source code (asm & C) a custom kickstart rom to use within WinUAE, not to use standard rom with patches.

[clebin]

Originally Posted by iliak

Hi pandy71

I'm sorry, I misspoke. I'm looking for how to build from source code (asm & C) a custom kickstart rom to use within WinUAE, not to use standard rom with patches.

There are open-source AROS replacement ROMs which are included with WinUAE now. You can get the latest source-code and binaries from the AROS nightly builds page http://aros.sourceforge.net/nightly1.php.

[Leffmann]

Originally Posted by iliak

Hi,

Does anyone ever tried to make a custom kickstart to replace orignal Amiga's ROM to use within WinUAE ? Any source code, toolchain, linker options ?

Thanks !

Yeah I've done this, it's pretty straight forward. I use vbcc and a simple Python script for building everything. I can write up a working example or just explain how it works if you'd like.

[pandy71]

Originally Posted by iliak

Hi pandy71

I'm sorry, I misspoke. I'm looking for how to build from source code (asm & C) a custom kickstart rom to use within WinUAE, not to use standard rom with patches.

Well... GIGO...

[Vot]

Originally Posted by Leffmann

Yeah I've done this, it's pretty straight forward. I use vbcc and a simple Python script for building everything. I can write up a working example or just explain how it works if you'd like.

I would like to see your working example

[iliak]

Originally Posted by Leffmann

Yeah I've done this, it's pretty straight forward. I use vbcc and a simple Python script for building everything. I can write up a working example or just explain how it works if you'd like.

Yes, please !

[HanSolo]

What exactly do you plan ? Rewrite entire kickstart to be fully optimized and patched/bugfixed ?

[iliak]

Hi HanSolo,

My plan is to make a custom ROM for the Amiga (as a hobby).

[iliak]

btw, for the toolchain => http://www.pouet.net/prod.php?which=65625

[Leffmann]

Here's a simple example that builds a ROM that does some basic initialization of the hardware and flashes the screen a bit.

You will need vbcc, Python 3, and GNU Make or something compatible.

[iliak]

I'll have a look. Thanks !

[iliak]

Originally Posted by Leffmann

Here's a simple example that builds a ROM that does some basic initialization of the hardware and flashes the screen a bit.

You will need vbcc, Python 3, and GNU Make or something compatible.

Some minor problems in the make file (spaces instead of tabs). I'm using the toolchain from https://github.com/kusma/amiga-dev and everything runs fine.

A little question. What is the purpose of your python script ? I guess it's related to this problem. Can you explain a little more please the array autovec values ?

[Leffmann]

The script is only used for adding the vector table and padding the ROM to 256KB size. The numbers are the little-endian 16-bit words 24 through 31, which are the correct vector numbers for the spurious interrupt and the level 1 through 7 interrupts.

[xArtx]

When you guys are building your own ROMs and make the compiled asm modules larger or smaller by changing them,
which would also shift the offset of each of them, is a jump table used for each build for the C code to reference the asm code at run time?
So that in the end, the C code calls a lookup table that directs program counter to the right vector?

Whether or not this speculation is correct,
I imagine a programmer could know this by having started out with the OS, and then graduated to not using OS for games and demos.

[Leffmann]

No lookups or tables are needed at run-time. The linker resolves all external references when building the final binary, and all calls between files/modules will be direct jumps, regardless of what language they were written in.

[xArtx]

Because that’s what a linker is! Doh!