ZX Interface 1
The ZX Interface 1 is a communications and storage interface for the ZX Spectrum released by Sinclair.
It provided an RS-232 serial interface, as well as storage using Microdrives and networking capabilities through the Sinclair Network, a proprietary interface of Sinclair's. The Sinclair Network would later be supported by MGT's DISCiPLE interface.
|0xf7||Read||TX Data||Net Input|
|Write||Net Output / RX Data|
|Write||Wait||CTS||Erase||R/W||Comms Clock||Comms Data|
|0xe7||Read||Microdrive data read|
|Write||Microdrive data write|
- TX Data is the value received by the serial port.
- Net Input is the value read from the Sinclair Network port.
- Bit 0 of port 0x7f is output to the serial port if Comms Data is set, or to the network port if Comms Data is reset.
- DTR signals that the remote station wishes to send data, CTS signals that the Spectrum wishes to send data
- Wait is used for network synchronisation.
- When Erase is reset the tape is erased and data is written, when set data is read.
- R/W instructs the microdrive to read or write. When R/W is set the microdrive runs, when reset it stops
- Comms Data is the value to be shifted into the microdrive select flip-flop chain.
- Comms Clock shifts the microdrive select bit along the chain.
- Write Protect is raised when a writeable cartridge is present in the selected microdrive.
- Gap and Sync are used to locate the correct block of data on the microdrive.