IBM System/23 Datamaster: Difference between revisions
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Video memory seems to be placed at address 8000h (to be confirmed).
=== I/O Ports ===
The Datamaster has a rich set of Intel peripherals which consist of a 8251 USART, 8253 PIT, three 8255 PPI, 8257 DMA, 8259 PIC and 8279 CRTC. All of them, including other devices are accessed the following ports:
{| class="wikitable"
! Ports !! Device
|-
| 20h-23h || Page registers
|-
| 24h-27h || PIT
|-
| 28h-2Bh || PIC
|-
| 2Ch-2Fh || 8255#3
|-
| 40h-43h || Service port
|-
| 44h-47h || CRTC
|-
| 48h-4Bh || USART
|-
| 4Ch-4Fh || Keyboard port
|}
=== Diagnostics ===
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