Fast data transfers circuit for telegram transmission - has direct memory access controller and read-write store associated with processor

摘要

In this data transmission circuit, which has fast data transfer rate, the data bytes, forming e.g. a telegram, are entered into a store of a micro-computer which holds instructions and data. The starting address is specified by the computer and the transmit instruction is entered into memory. The memory is continuously interrogated by the computer. Data from computer (1) are entered via a register (2) into a read/write store (7c) which is associated with a processor (7a) and ROM (7b) containing the instructions. At the same time control data for direct memory access are issued to a control circuit (3) and the starting address in the store (7c) is entered into a register (4). Processor action is suspended during direct memory access.