By Bob Applegate
Adding I/O devices that don’t need much address space. On the KIM-1, the space from 1400-17FF is grouped into the K0 block but only 17xx are used, leaving 1400-16FF open for use. To decode that range into four blocks of 256 bytes is easy using a single chip and a few signals from the KIM Clone expansion bus:
Everyone has a 74LS138 in their parts collection, so just connect a few signals from the expansion bus and use one of the three signals from the 138 to decode which block you want to use. Use the A0-A7 address lines to decode into smaller pieces.
See also:
aim65_quartus
Filippo (shinymetal6) published an alpha version of aim65_quartus, an FPGA clone on his github resource. Forum discus...
Filippo (shinymetal6) published an alpha version of aim65_quartus, an FPGA clone on his github resource. Forum discus...
TIM-1 SBC
Christian Ortner (mister-freeze at the VzEkC e. V. forum buold a SBC with expansion around a TIM IC. Here is his proje...
Christian Ortner (mister-freeze at the VzEkC e. V. forum buold a SBC with expansion around a TIM IC. Here is his proje...
MC-65
An AIM 65 compatible 65C02 CPU based computer, the MC-65. With a 6532, 6522, terminal I/O, cassette interface, and in th...
An AIM 65 compatible 65C02 CPU based computer, the MC-65. With a 6532, 6522, terminal I/O, cassette interface, and in th...
AIM 65 reproduction AIM65-CPLD-3v3
Mr. Nagano, from Tokyo, Japan send me photos and circuit diagram of an AIM 65 reproduction he designed an build: the AIM...
Mr. Nagano, from Tokyo, Japan send me photos and circuit diagram of an AIM 65 reproduction he designed an build: the AIM...