CP/Mega88 is the brainchild of Takashi Toyoshima <toyoshim@gmail.com>

This version only supports the AVR based system, with native 'disks', no FAT base image files.

It has been modified to support 128 kByte of SRAM, hardware handshake (receiving) for the serial terminal, SDSC and SDHC SD cards and up to 254 8 Mbyte diskvolumes to be mounted on the B: and C: drives.
It may boot into CP/M 2 or CP/M 3, which are installed on diskvolume 2 and 3 respectively

The circuit board provides an FTDI compatible serial interface, using RxD,TxD and RTS signals, operating at 38400 baud 8 bits no parity. Use 2 stopbits for maximum stability.
Power may be applied by the FTDI compatible interface or via a separate 5v connector. 
Power draw is about 10 mA. External system reset via the RESET connector. 
The serial interface has voltage converters. External signal voltage levels are determined by the applied power in voltage. Internally 3v3 is used troughout. 

AVR programming is achieved by using the included ISP2SD converter in the SD-card slot while bridging the PRG jumper on the backside of the board. The programmer may use 5v because the SD-card will not be present. Remove the jumper before using the SD-card again. The most convenient way is to use metal tape for this, or a piece of aluminium foil, particularly is you have to do this repeatedly.
