Changes

After a seller goes out of business or stops supporting a product line, before IPs (Instruction set Processors) like [[CPLD]] or [[FPGA]], they essentially became unavailable. [[Commodore_64#ICs|Commodore]] used a plethora of ASICs in their machines (VIC, SID, PAULA,......); [[MSX]] or the [[IBM PC]]/XT/AT were the opposite in using only [[COTS]] components, making it easy for third parties to offer parts (or to re-build and repair the computers for as long as the COTS chip was still available or a backwards-compatible component exists).

==Amstrad Custom chips==

CPC+ ASIC's part number is 40489

==Emulated chips==

* Printer Port Data and Strobe

* Floppy Motor enable [[flip-flop]], Floppy Address decoding (FDC chip Select)

==New features==

*Specific ROM switching

*8-bit printer port (with bit3 of CRTC register 12)

== DMA commands ==

* The STOP instruction will leave the source address register pointing to the next instruction, so that the instruction stream can be continued after CPU intervention.

* The argument field (N) of the REPEAT instruction is actually the number of times the loop is taken. The block of code between REPEAT and LOOP instructions is therefore executed N+1 times.

== Known Flaws==

*Original CPC colors emulation is not correct.

==Internal Links==

*[[CRTC]]

*[[Gate Array]]

==External Links==

*[http://www.cpctech.org.uk/docs/cpcplus.html Extra Plus Hardware Information]

*[http://quasar.cpcscene.net/doku.php?id=assem:asic Quasar ASIC documentation (in french)]

[[Category:CPC Plus|*]][[Category:Electronic Component]][[Category:Programming]][[Category:Datasheet]][[Category:Graphic]]

[[Category:Stub]][[Category:CPC Internal Components]]