Peripheral 4 Setting Register
From SpecNext Wiki
(Redirected from NextReg:$09)
| Next Register Number | $09 |
|---|---|
| Readable | Yes |
| Writable | Yes |
| Short Description | Sets scanlines, AY mono output, Sprite-id lockstep, reset DivMMC mapram and disable HDMI audio. |
| Bit | Function |
|---|---|
| 7 | Enables AY2 "mono" output (A+B+C is sent to both R and L channels, makes it a bit louder than stereo mode). |
| 6 | Enables AY1 "mono" output (1 = mono, 0 default) |
| 5 | Enables AY0 "mono" output (0 after Hard-reset) |
| 4 | Sprite id lockstep (1 = NextReg:$34 and NextPort:$303B are in lockstep, 0 default) |
| 3 | 1 to reset mapram bit in DivMMC
(was "Disables Kempston mouse port ($DF)" in core 2.0) |
| 2 | 1 to silence HDMI audio (hard reset = 0) (since core 3.0.5)
(was "Disables divMMC ports ($E3, $E7, $EB) if set" in core 2.0) |
| 1-0 | scanlines weight (0 after Hard-reset):
(since core3.1.1) %00 = scanlines off, %01 = scanlines 50%, %10 = scanlines 25%, %11 = scanlines 12.5% |