Changes
/* CPC Schneider International - 8 bit Printer Port Mod */
The CPC [[Printer Port]] has only 7 bit data. Which is sufficient for english English 7 bit ASCII character sets, but not enough for 8 bit character sets. Also, printing bitmap graphics usually requires 8 bit data (though usually can also print 7 pixels columns combined with a reduced line-feed rate). Amstrad's DMP1 works perfectly with 7 bit, but Amstrad's later DMP2000/DMP2160 include a few functions that won't work on 7 bit ports - so even the official CPC printers aren't fully compatible with the CPC printer port. There's a software solution though, proposed by [[Amstrad Computer User]] using a replacement driver (only for printers accepting EPSON control codes).
== Internal 8 bit Printer Ports/Mods ==
=== CPC Schneider International - 8 bit Printer Port Mod ===
DIY from [[CPC Schneider International]] (issue 12'85, page 64), this solution uses joystick port pin 8 (or (keyboard?) connector pin 2, unclear?). Both PINs are connected to Pin 11 of the 74LS145 Decoder.This fix can be implemented completely external with a cable from Joystickport to the Printercable without any modification on the CPC itself required. However also a permanent internal connection can be created.
* For details see: [[CPCI 8bit Printer Mod]]
=== 8 bit Printer Port in KC Compact ===
The [[KC Compact]] uses the bit 5 of [[8255|PPI]] Port C as 8th printer bit (this is same as the Happy Computer mod, see above). Although the 8th bit is a built-in feature, the KC Compact OS Firmware doesn't support it. But it's supported by [[FutureOS]].
=== 8 bit Printer Port in Aleste 520EX ===
=== 8 bit Printer Port in CPC Plus ===
In the CPC Plus, Bit 3 of [[CRTC]] Register 0Ch can be used as eighth printer bit. For compatibility to normal CPCs, this feature can be disabled by removing the 10 kOhm resistor R30 on the mainboard (aka R130 in the schematic). See [[LK Links]] for more info. Although the 8th bit is a built-in feature, the CPC Plus BASIC/OS Firmware doesn't support it. However the 8 bit printer port of the CPC Plus is supported by [[FutureOS]].
== External Printer Ports ==
* [[8bit Printer Port (Amstrad Action)]] (DIY) - connects to Expansion Port (uses Port FBF8h/FBF9h)
* [[8bit Printer Port (Paul Bauriedl)]] (DIY) - connects to Printer Port (splits port EFxxh to 2 x 4 bit)
* [[BrunWord|BrunWord's Eight Bit Status port]] - connects to Printer Port (splits port EFxxh to whatever, details are unknown)
* [[CPCI 8bit Printer Mod]] (DIY) - connects bit 7 to Joystick_1_Select signal (can be connected internally or externally)
* [[CPCISA by Yarek]] can be used with various ISA bus printer cards (8bit, one- or bi-directional types, SPP, XPP, EPP, etc.)
* [[Panda Electronics Communications Interface Unit]] (dual RS232 plus PPI-based 8bit printer port) (Panda Electronics Ltd)
* [[RS232|RS232 Interfaces]] (various manufacturers) - can be used to access RS232-compatible printers with full '''8 bit''' support
* [[Schneiderware Centronics Port]] - connects (via a separate motherboard) to Expansion Port (uses a [[8255 PPI chip]])
Also, reportedly, the following external hardware exists:
* 8 bit Printer Port with 16 bit I/O port ([[HoneySoft]]) (see [[Media:Amstrad Computer User8509037.jpg|advert]])
== See also ==
* [[Amstrad/Schneider Printer Support for 7bit Printer Ports]]
[[Category:HardwarePrinters and printer ports]] [[Category:DIY]]
