Portable_Control Mask (changes)
Showing changes from revision #4 to #5:
Added | Removed | Changed
Portable
» SWI Calls
» Portable_Control
» Mask
Mask
Mask
| Bit | Meaning when set |
|---|---|
| 0 | Econet power enabled |
| 1 | LCD display power enabled |
| 2 | External video display power enabled |
| 3 | Serial buffer and oscillator power enabled |
| 4 | Dual panel mode |
| 5 – 6 | Video clock control: |
| 0 = external clock | |
| 1 = crystal / 2 | |
| 2 = crystal | |
| 3 = reserved | |
| 7 | Invert video clock |
| 8 | Enable back light |
| 9 | Display has 2 extra lines (else 1 extra) |
| 10 | 2 DRAMs used for dual panel (else 1) |
| 11 | Sound filters and amplifiers power enabled |
| 12 | PCMCIA interface power enabled |
| 13 | Parallel port power enabled |
| 14 | FDC oscillator power enabled |
| 15 | IDC hard disc power enabled |
| 16 | LCD palette set for inverse video |
| 17 | Internal trackball in use |
| 18 | External mouse in use |
| 19 | External keyboard and mouse power enabled |
| 20 – 31 | Reserved, must be zero |
Notes
Changing bits 0, 3, 14 will generate Service_Portable.
The 82C711 in the A4 shares one oscillator – this will only be powered down if bits 3 & 14 are both clear. On some machines the oscillator is used by other parts of the system and can never be powered down.
Bits 17 and 18 are mutually exclusive.
Not all control bits are available in all versions of the module; see the see Portable the Feature feature Matrix matrix.
See also
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