Editing IBM System/23 Datamaster (section)

=== Peripheral Chipset (all Intel, relabelled with IBM part numbers) ===

* '''8257 DMA''' — with a dedicated channel for floppy transfers (the 8275 CRTC has no internal address generator and uses DMA for every frame).
* '''8275 CRTC''' — 80 × 24 character display.
* '''8253 PIT''' — programmable interval timer.
* '''3 × 8255 PPI''' — general-purpose parallel I/O (one of them drives the diagnostic probe port at the rear).
* '''8251 USART''' — single async/sync serial channel.
* '''8259 PIC''' — programmable interrupt controller.
* '''8048''' in the keyboard — with Datamaster-specific firmware.
* '''NEC 765 FDC''' on the floppy controller card.