Ashet Home Computer Specification

DISCLAIMER: This is a living document, do not take anything here for granted!

Hardware

CPU

  • SPU Mark II, a 16 bit processor

Memory

  • 8 MB of flash
  • Up to 8 MB of ram

Peripherials

  • VGA video
  • 4 serial ports
    • 2 * RS232
    • 1 * USB Serial
    • 1 infrared serial interface for wireless data transfers
  • 2 PS/2 ports for keyboard and mouse
  • 2 IDE slots for mass storage
  • 2 (digital) joystick ports, compatible to c64/amiga/cpc/…
  • IEEE 1284 II parallel port
  • PCM audio interface
  • Real time clock
  • 10 MBit Ethernet
    • Possibly based on ENC28J60 or ENC624J600

Memory Map

Address Range Memory Type Component
0x0***** (Memory) up to 8 MB Flash ROM
0x7FE*** (Peripherial) I/O Page
0x7FF*** (Peripherial) VGA Sprite Data
0x80**** (Memory) up to 8 MB of RAM

The I/O Page contains all peripherial registers and links to the peripherial devices.

DMA Devices

The following devices have memory access (with priority top-to-bottom):

  • VGA Controller
  • Audio Controller
  • CPU
  • DMA Controller

IRQ Table

IRQ Number Peripherial
0 COM1
1 COM2
2 COM3
3 COM4
4 PER1
5 PER2
6 PCM
7 DMA
8 TIMER0
9 TIMER1
10 VGA
11 ETHERNET
11 … 31 unused

Serial Ports

COM Name Connector Base Address
COM1 USB (TBD)
COM2 RS232 1 (TBD)
COM3 RS232 2 (TBD)
COM4 IR (TBD)

PS/2 Ports

Function Connector Base Address
PER1 KEYBOARD (TBD)
PER2 MOUSE (TBD)

Timers and RTC

Timer 0 runs at 1 MHz, Timer 1 runs at 1 kHz.