| 摘要 |
Data are transferred from an electronic equipment to an additional control device without any signal line for transferring the data. An electronic equipment to which data are transferred, e.g., an electronic control equipment in a printer outputs the data to be transferred by reflecting the data in the lower order eight bits of an address signal line (CAB). By this assignment of an address, the data corresponding to the address is read out from a ROM (671), and is latched by latches (651, 652), and further, the additional control device is informed of the latching of the data by a signal EWRDY. When a microprocessor of the additional control device, i.e., a cartridge reads the data latched in the latches (651, 652) via a data bus (DB29), the data transfer from the electronic equipment is completed. Even in the case of the absence of the data bus or in the case of a read only line, the data can be transferred to the additional control device, and be processed on the side thereof. |
