Machine Type Register
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Revision as of 19:45, 20 December 2018 by wiki>Ped7g (Making this more in sync with web docs about ports, and removing non-existent links.)
| Number | $03 |
|---|---|
| Readable | Yes |
| Writable | Yes |
| Short Description | Identifies timing and machine type. |
Only valid in IPL or config mode (0x0000-0x3FFF are mapped to the RAM instead of the internal ROM).
A write in this register disables the IPL.
| Bit | Function |
|---|---|
| 7 | Lock Timing |
| 6-4 | Timing. %000-001: ZX 48k; %010: ZX 128k/+2 (Grey); %011: ZX +2A-B/+3e/Next Native; %100: Pentagon. |
| 3 | Reserved, must be 0 |
| 2-0 | Machine type. %000: Config mode; %001: ZX 48k; %010: ZX 128k/+2 (Grey); %011: ZX +2A-B/+3e/Next Native; %100: Pentagon. |