ULA Control Port: Difference between revisions

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When written to, adjusts the border color and audio devices as follows:
When written to, adjusts the border color and audio devices as follows (soft reset = 0):


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{| class="wikitable"

Revision as of 00:34, 16 April 2020

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

When written to, adjusts the border color and audio devices as follows (soft reset = 0):

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 {{#ask: PortNumber::$**FE }} ($**FE{{#ask: PortNumber::$**FE |mainlabel=- |headers=hide |intro= /  |?NumberDec#- }}). 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).