Programming ROMs (BBC Micro)
All BBC Micro come with sockets inside where you could install up to 4 ROM chips.
If you wanted to program your own today, you can use an XGPro programming device such as the T48 or T56, and AT28C256 EPROM chips (which are 32k not 16k like the originals), so you would double up your ROM files and program the same ROM into the both top and bottom 16k banks of the chip.
All ROMs can be downloaded here.
As they are 16k ROMs and we will be programming them onto 32k ROMs we want to double the contents up. Do that using command line and copy /b romname.bin + romname.bin output.bin where romname is the name of the ROM you want to use, and output.bin is the output filename of the 32k version you can then program onto the 27C256.
Some ROMs are only 16k such as Disc Doctor. For those copy the file 4 times so the final file is 32k.
The BBC Master 128 (the model with 128k RAM and the M logo at the front right) doesn't use the same ROMs in the sockets.
Instead, the BBC Master system ROM is a single 128K ROM in a 28-pin package. It holds the MOS and sideways ROMs 9 to 15. ROMs 15 and 14 hold extra parts of the MOS, but ROMs 9 to 13 can be freely replaced with other sideways ROMs.
More details about the ROM layout of the Master 128 can be found here.
Unfortunately this means it is a 1MBit chip (and the largest standard pinout chip the 27C256 is only 256KBit).
Solutions to this use the AM29F040B which is a 4MBit chip, and 4 switches to 4 full banks of 1MBit, such as the RetroClinic BBC Master 128 MultiOS.
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