* Seikosha GP500AT-1 - Was offered as '''Atari 1029''' for Atari XL (dual 13pin port) ([[:File:Atari1029 Printer.jpg|printer photo]], [[:File:Atari1029 PCB.jpg|pcb photo]]) (no 2K SRAM) (BIOS: 8AT-1)
The main difference is that the PCBs are customized - the VC and AT models have non-centronics connectors. The ROMs might be also customized, possibly containing different character sets (?), and most probably different protocols (for the serial-port VC version at least). Some versions include 2K SRAM buffers, others don't. The Commodore version supports inverse mode, the CPC doesn't support this.
Note: The name "Seikosha GP 500M-2" is printed on the PCB, in the internet, it's often referred to as "Seikosha GP 500 CPC".