Difference between revisions of "Peripheral 2 Register"

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(core 3.0 changes/refresh)
(summary enriched)
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|Readable=Yes
 
|Readable=Yes
 
|Writable=Yes
 
|Writable=Yes
|ShortDesc=Enables [[Acceleration]], [[DivMMC]], [[Multiface]], [[Mouse]] and [[AY]] audio.
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|ShortDesc=Enables [[Acceleration|Acceleration key]], [[DMA|DMA mode]], [[DivMMC]], [[Multiface]], [[Mouse]] and [[AY|AY audio]].
 
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{| class="wikitable"
 
{| class="wikitable"

Revision as of 18:10, 11 December 2019

Number $06
Readable Yes
Writable Yes
Short Description Enables Acceleration key, DMA mode, DivMMC, Multiface, Mouse and AY audio.
Bit Function
7 Enable turbo mode key "F8", 0 = disabled (1 after Soft-reset)
6 DMA mode (0 = zxnDMA, 1 = Z80 DMA) (0 after Hard-reset)
5 Enable "F3" key (50/60 Hz switch) (1 after Soft-reset) (was "Enable Lightpen" in core 2.0)
4 Enable DivMMC automap and DivMMC NMI by DRIVE button (0 after Hard-reset)
3 Enable Multiface (1 = enabled) (0 after Hard-reset)
2 PS/2 mode (primary device: 0 = keyboard, 1 = mouse), exchanges the keyboard/mouse pins on the PS/2 connector (writeable only in config mode)
1-0 Audio chip mode (%00 = YM, %01 = AY, %1x = Disabled)

(core 3.0) %11 hold all AY in reset

The bit 7 doesn't prevent SW from setting up turbo mode by writing into CPU Speed Register ($07), it is used only to enable/disable the "F8" key toggle, similarly bit 5 enables "F3" key.

NEW in core 3.0:

 bit 5 = enable F3 (50/60 Hz)
 bit 2 ps2mode only modifiable in config mode
 chip mode = 11 resets all AY