520 STFM C070789-001 Rev F2

[exxos]

Thank you for this, I just noticed the 2 chip 1.4’s are out of stock at present. Can these be re-wrote on mine or shall I just wait for them to come back in stock?

2 chip cannot be created or reprogrammed, they are special chips which I can only get from original machines. As already suggested, a DUALTOS board would be a suitable replacement... Or downgrade to 6 chip TOS.

[rubber_jonnie]

I personally go for a 6 chip set every time I upgrade. as @exxos said, the 2 chip sets tend to be mask ROMs and can't be re written, and you can't make new.

27C256 EPROMS are easily available, so I burn my own. Probably your best solution is the dualTOS board.

[friijy2001]

Thank you for this, I just noticed the 2 chip 1.4’s are out of stock at present. Can these be re-wrote on mine or shall I just wait for them to come back in stock?

2 chip cannot be created or reprogrammed, they are special chips which I can only get from original machines. As already suggested, a DUALTOS board would be a suitable replacement... Or downgrade to 6 chip TOS.

Thank you for that, I’ll probably go with the dual TOS version then