Why not just dump it out of the M100 directly?
On Tue, Nov 28, 2023 at 9:50 AM Brian K. White <[email protected]> wrote: > > On 11/27/23 11:48, runrin wrote: > > Do you know if it's possible to dump the original ROM using the > > programming adapter for the FlexROM 100? > > Maybe. > > There are two things to worry about and I'll just think out loud right here. > > 1 > The programming adapter presents a pinout for a 28C256, not a 27C256 or > mask rom. Those are only a couple wires different, but then again, since > it's just for reading, and the read cycle is the same, you could just > tell the programmer that it's reading a 28C256 (force it, override chip > id detection), and that won't hurt the rom. > > 2 > Pin 23. The programming adapter routes pin 27 from the programmer (/WE > if a 28C256 were in the programmer) to pin 23 of the DIP socket, which > is ALE on the LH535618 rom, but the flexrom board connects it to the /WE > pin on the actual 28C256 on the board. > > I *think* what you want to do is take a DIP-28 socket and bend out pin > 23, connect the bent-out pin 23 to pin 27, put the modified socket into > the programming adapter and then the old rom into the modified socket. > Then tell the programmer to read a 28C256 and ignore chip id. The socket > is just to avoid bending the leg on the old chip. > > IE, feed /CE from the programmer to both /CE and ALE on the chip, and > don't connect anything to /WE at the programmer. > > But, at that point it's almost simpler to just make the entire adapter > manually with two dip sockets and wires. Especially since it's a > one-off. In that case, use a 27C256 pinout and tell the programmer to > read a 27C256 instead of 28C256. > > But if your chip has any of these part numbers, then it's already been > dumped. > https://bitchin100.com/wiki/index.php?title=Model_and_ROM_information > > -- > bkw >
