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13:29, 30 March 2010 PDS is an acronym for "Professional Development System" and is a hardware setup for cross development.
Code was developed on another computer, in this case a PC, and downloaded to the target computer (e.g. Amstrad).
The target computer had additional hardware and program which waited for the PDS host to send information.
The host would send "instructions" to the target computer.
==Technical==
Uses port FBEC-FBEF.
FBED input is used to signal data is ready for CPC to read
FBEC is used to transfer 8-bit data.
FBED output is used to signal back to host that data has been received.
Not known what the interface contained.