ROM Image Editor

[valentin]

Hello,

I need to write the ZX Spectrum 48K ROM into four 2732 EPROM's (Mitsubishi M5L2732K). I assume I need to find a "way" to split the 16384 bytes "48k.rom" file into four files of 4096 bytes each. What Windows / Linux / macOS program shall I use to achieve this?

[dr beep]

Why not export a binairy block from an emulator?

[Paul]

This heavily depends on which organisation the new 4x4K ROMs will have.
Example:
Rom1: 0-4K
Rom2:4-8K
Rom3:8-12K
Rom3:12:16K
This can be achieved with a good editor like ultraedit by deleting the respective parts
Rom1:bytes 1,3,5,7,9..... of 0-8K
Rom2:bytes 2,4,6,8..... of 0-8K
This can be achieved with programming tools that come with eprommer.

And so on.
If your programmer can't do these operations,
Just contact me via PM and I will do this for you.
Kind regards Paul

[Paul]

I just saw you have the same eprommer as I have TL866CS. I can guide you through its programming options to show you how to achieve what you want.
We can do a video call with screen sharing if you like.

[valentin]

Many thanks for your feedback.

@Paul, I don't have the TL866CS; I was looking to get one, until I discovered that, with help from some adapters, I can use my Retro Chip Tester as an EPROM programmer.

I don't know yet how viable this solution is and how well it works, but I will find out soon enough (the PCB's arrived from China weeks ago and all the components are waiting to be soldered).

I am very grateful for your offer to help "quartering" the 16K ROM - I will take advantage of it

The 4K EPROM's I have are organized as 4096 x 8-bit. As for the how the whole 16K will be organized... I am not sure, but I think your assumption (ROM1: 0-4K, ROM2: 4-8K, etc) is correct. Will it help to add that these four chips will be installed in ZX Spectrum Romanian clone (HC 85)? They originally shipped with 8x 2K EPROM's (2716) or PROM's (2616) - see the diagram link below; and I remember seeing boards with 4x 4K EPROM's.

ROM diagram

[kolbeck]

Being very late to this - but maybe this tip can help someone else in the future.

On Unix/macOS - just use the command split (part of GNU coreutils). On macOS use Homebrew to install coreutils.

split -b 4096

and the result is nicely numbered files of 4096 bytes each.