Changes
The Amstrad CSD was a machine that was in-store to demonstrate the hardware of the Amstrad plus.
It had a system cartridge which contained a menu, and could hold a furthur further 12 cartridges.
It has additional hardware to allow switching of cartridges.
Lots of information is not known at this time.
It uses ports fbe0-fbe3. The exact decoding and operation of these ports is unknown.
fbe0 This port is read only it seems. bits 7..4 seem to be related to the dip switches on the CSD with bit 7 seems to be fixed to GND/0v.
bit 6,5 is the timer value. It is the time allowed between choosing next cartridge to play.
bit 6, bit 5
off off = 8s 1 1
off on = 16s 1 0
on off = 24s 0 1
on on = 32s 0 0
bit 4 seems to be timer on/off for time limited play.
bits 3..0 are defined by the dial
bit 3 is ignored.
0 = forever?
1 = 8s,
2 = 56s
fbe2 is read only it seems bits 7..3 are the currently selected cartridge bits 3..0 ??? fbe1 is writeable bits 7,6: ??? bits 5..0: are cartridge number?? fbe3 is writeable: bits 7..4: are cartridge number bits 3..0: ???
== The CSD System Cartridge ==
It is believed the others are for a rolling demonstration mode, and a play mode that is limited.
The only cartridge to have this header is [[Pang (cartridge)|Pang]].
== Pictures ==
