PCBgogo

*** No worries with PCBGOGO, the board in 12 days after online delivery of the files (Belgium). The quality is excellent and neat. The silk printing is fine and absolutely readable. Even the 2mm fonts are perfectly printed. If you have other than round holes PCBGOGO does the job nice and clean. All components fit snuggly without issues. I chose the standerd PCB material with a thickness of 1.6 mm which feels strong, very much usable as a frame for a loading carrying toy however that's not my intention. *** - The design foresaw in a fully accessible Z80 bus, MIDI interface and TTL COM interface. - Data protection for non-volatile functioning of the RAM. - (E)EPROM/RAM paging in steps of 2K with the bottom 2K fixed to (E)EPROM. - (E)EPROM up to 64K, RAM up to 64K configurable with jumpers according to capacities of memory chips used. - Wait state selectable for as well ROM as RAM (you never know). - Intel 8251 used as UART. UART TTL levels port separately accessible next to MIDI interface implementation of the data stream. - Z80 CPU system clock divider for /1, /2, /4 and /8. UART RxTx clock switchable by software between 2 available crystal time bases. - On board 12 volts to 5 volts stabilizer with diode polarization protection. 12 volts adapter socket and 12 volts connector. - Probably a practical basic computer system tool for educational purposes for nowadays since Arduinos are still kind of obscure in their design.

- This Z80 PLATO Universal board can handle any static RAM and any ROM up to 64K by use of jumper settings. - ROM/RAM pages can be configured via jumpers in 2K pages. The bottom 2K is fixed to ROM. ROM/RAM paging includes address folding. - The Z80 PLATO board has 2 time bases. One for the CPU and one for the Intel 8251 UART. The UART TxRx clock can be assigned to either time bases. The Z80 CPU system clock can be divided into 1,2,4 and 8 via jumpers. - On board classic MIDI in and MIDI out interface and classic TTL COM interface. - The board has 2 wait state jumpers. One for ROM and one for RAM (you never know). - The Z80 bus is fully accessible. - Local input output decoded select pins are provided for convenience, no external decoding for I/O necessary. 2 local input output addresses are reserved for the Intel 8251 UART chip on the board. - On board 12 volts (polarisation diode protected) to 5 volts stabilizer. - On board non-volatile RAM guard and watch dog chip.

The board includes a few logic to activate or deactivate two solenoids connected to the outputs. The 24V solenoids are driven from an output power MOSFET .