Difference between revisions of "Peripheral 2 Register"

Latest revision as of 11:02, 3 November 2024

Number	$06
Readable	Yes
Writable	Yes
Short Description	Enables CPU Speed key, DivMMC, Multiface, Mouse and AY audio.

Bit	Function
7	Enable CPU speed mode key "F8", and F5/F6 expansion bus hotkeys 0 = disabled (1 after Soft-reset)
6	core3.1.2: Divert BEEP-only to internal speaker (hard reset = 0) ~~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 NMI by DRIVE button (0 after Hard-reset)
3	Enable multiface NMI by M1 button (hard reset = 0)
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, %10 = ZXN-8950, %11 = Hold all AY in reset) (core 3.0) %11 hold all AY in reset

The bit 7 doesn't prevent SW from setting up different CPU speed 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

NEW in core 3.1.2:

 bit 6 = BEEP-only into internal speaker (DMA does use two I/O ports now)

@@ Line 3: / Line 3: @@
 |Readable=Yes
 |Writable=Yes
-|ShortDesc=Enables [[Acceleration]], [[Lightpen]], [[DivMMC]], [[Multiface]], [[Mouse]] and [[AY]] audio.
+|ShortDesc=Enables [[CPU Speed control|CPU Speed key]], [[DivMMC]], [[Multiface]], [[Mouse]] and [[AY|AY audio]].
 }}
 {| class="wikitable"
 ! Bit !! Function
 |-
-| 7 || Enable turbo mode key "F8", 0 = disabled (0 after PoR or Hard-reset)
+| 7 || Enable CPU speed mode key "F8", and F5/F6 expansion bus hotkeys 0 = disabled (1 after Soft-reset)
 |-
-| 6 || DMA mode (0 = zxnDMA, 1 = Z80 DMA) (0 after PoR or Hard-reset)
+| 6 || core3.1.2: Divert BEEP-only to internal speaker (hard reset = 0)
+<del>DMA mode (0 = zxnDMA, 1 = Z80 DMA) (0 after Hard-reset)</del>
 |-
-| 5 || (core 2.0) Enable Lightpen (1 = enabled) (0 after PoR or Hard-reset)
+| 5 || Enable "F3" key (50/60 Hz switch) (1 after Soft-reset) (was "Enable Lightpen" in core 2.0)
-(core 3.0) Enable "F3" key (50/60 Hz switch)
 |-
-| 4 || DivMMC automatic paging (1 = enabled) (0 after PoR or Hard-reset)
+| 4 || Enable DivMMC NMI by DRIVE button (0 after Hard-reset)
 |-
-| 3 || Enable Multiface (1 = enabled) (0 after PoR or Hard-reset)
+| 3 || Enable multiface NMI by M1 button (hard reset = 0)
 |-
-| 2 || PS/2 mode (0 = keyboard, 1 = mouse), exchanges the keyboard/mouse pins on the PS/2 connector (0 after PoR or 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)
-(core 3.0) can be modified only in "config" mode
 |-
-| 1-0 || Audio chip mode (%00 = YM, %01 = AY, %1x = Disabled)
+| 1-0 || Audio chip mode (%00 = YM, %01 = AY, %10 = ZXN-8950, %11 = Hold all AY in reset)
-(core 3.0) %11 resets all AY (not sure how is that different from %10, TBD)
+(core 3.0) %11 hold all AY in reset
 |}
-The bit 7 doesn't prevent SW from setting up turbo mode by writing into {{NextRegNo|$07}}, it is used only to enable/disable the "F8" key toggle (core 2.00.24 information).
+The bit 7 doesn't prevent SW from setting up different CPU speed by writing into {{NextRegNo|$07}}, it is used only to enable/disable the "F8" key toggle, similarly bit 5 enables "F3" key.
 '''NEW in core 3.0:'''
@@ Line 33: / Line 32: @@
    bit 2 ps2mode only modifiable in config mode
    chip mode = 11 resets all AY
+'''NEW in core 3.1.2:'''
+  bit 6 = BEEP-only into internal speaker (DMA does use two I/O ports now)