This Cartridge PCB uses only one ROM from HITACHI named HN613256P. This chip is a CMOS Mask Programmable Read Only Memory, designed especially for use in a bus-organized systems.
Its built in memory matrix has 32,768 x 8bit word, which means 32 Kbytes of data available. It has an address decoder which interfaces directly to the computer through cartridge connector and a 3-State Output Buffer for data output which is driven by two signals by the computer.
There are two Selectors-Multiplexers DM74LS157, one SN74S32N POSITIVE-OR MULTIPLE GATE and two 16,384-word by 4-bit dynamic RAM ( 8Kbytes x2 )