Difference between revisions of "ULA Control Port"

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(adding info)
Line 4: Line 4:
 
|Readable=No
 
|Readable=No
 
|Writable=Yes
 
|Writable=Yes
|PortMask=%---- ---- ---- ---0
 
 
}}
 
}}
 
When written to, adjusts the border color and audio devices as follows:
 
When written to, adjusts the border color and audio devices as follows:
Line 13: Line 12:
 
| 0-2 || Border color
 
| 0-2 || Border color
 
|-
 
|-
| 3 || Enable MIC output
+
| 3 || MIC output (saving via audio jack)
 
|-
 
|-
| 4 || Enable EAR output
+
| 4 || EAR output (connected to internal speaker)
 
|-
 
|-
 
| 5-7 || Unused
 
| 5-7 || Unused
 
|}
 
|}
  
Reading the port with certain particular high bytes will read the keyboard - see {{PortNo|$**FE}}. Bit 6 of the ULA byte is always the EAR input.
+
---------
 +
 
 +
Reading the port with certain particular high bytes will read the keyboard - see {{PortNo|$**FE}}. Bit 6 of the ULA byte is always the EAR input (signal from tape audio jack - also input from [https://wiki.specnext.dev/Pi:index Pi] digital audio is now mixed in, since 3.0 cores).

Revision as of 09:37, 31 December 2019

Number $xxFE
Decimal
Short desc. Controls border color and base Spectrum audio settings.
Bit Mask
Readable No
Writable Yes
Subsystem

When written to, adjusts the border color and audio devices as follows:

Bit Function
0-2 Border color
3 MIC output (saving via audio jack)
4 EAR output (connected to internal speaker)
5-7 Unused

Reading the port with certain particular high bytes will read the keyboard - see Keyboard ($**FE / 254). Bit 6 of the ULA byte is always the EAR input (signal from tape audio jack - also input from Pi digital audio is now mixed in, since 3.0 cores).