Difference between revisions of "Peripheral 4 Register"

Revision as of 12:34, 11 November 2019

Number	$09
Readable	Yes
Writable	Yes
Short Description	Sets scanlines, AY mono output, Sprite-id lockstep, disables Kempston and divMMC ports.

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 = Sprite port-mirror Index Register ($34) and Sprite Status/Slot Select ($303B / 12347) are in lockstep, 0 default)
3	1 to reset mapram bit in DivMMC (was "Disables Kempston mouse port ($DF)" in core 2.0)
2	Reserved, use 0 (was "Disables divMMC ports ($E3, $E7, $EB) if set" in core 2.0)
1-0	scanlines weight (0 after Hard-reset): %00 = scanlines off, %01 = scanlines 75%, %10 = scanlines 50%, %11 = scanlines 25%

@@ Line 12: / Line 12: @@
 | 6 || Enables AY1 "mono" output (1 = mono, 0 default)
 |-
-| 5 || Enables AY0 "mono" output
+| 5 || Enables AY0 "mono" output (0 after Hard-reset)
 |-
 | 4 || Sprite id lockstep (1 = {{NextRegNo|$34}} and {{PortNo|$303B}} are in lockstep, 0 default)
 |-
-| 3 || (core 2.0) Disables Kempston mouse port ($DF) if set
+| 3 || 1 to reset mapram bit in DivMMC
-(core 3.0) 1 to reset mapram bit in divmmc
+(was "Disables Kempston mouse port ($DF)" in core 2.0)
 |-
-| 2 || (core 2.0) Disables divMMC ports ($E3, $E7, $EB) if set
+| 2 || Reserved, use 0
-(core 3.0) Reserved, use 0
+(was "Disables divMMC ports ($E3, $E7, $EB) if set" in core 2.0)
 |-
-| 1-0 || scanlines configuration (0 after a PoR or Hard-reset):
+| 1-0 || scanlines weight (0 after Hard-reset):
 %00 = scanlines off, %01 = scanlines 75%, %10 = scanlines 50%, %11 = scanlines 25%
 |}