Display Control 1 Register

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Number TBRegisterNumber::$69
Readable TBRegisterReadable::Yes
Writable TBRegisterWritable::Yes
Short Description ShortDesc::Layer2, ULA shadow, Timex $FF port
Bit Function
7 Enable the Layer 2 (alias for {{#ask:

PortNumber::$123B }} ($123B{{#ask: PortNumber::$123B |mainlabel=- |headers=hide |intro= /  |?NumberDec#- }}) bit 1)

6 Enable ULA shadow (bank 7) display (alias for {{#ask:

PortNumber::$7FFD }} ($7FFD{{#ask: PortNumber::$7FFD |mainlabel=- |headers=hide |intro= /  |?NumberDec#- }}) bit 3)

5-0 alias for {{#ask:

PortNumber::$xxFF }} ($xxFF{{#ask: PortNumber::$xxFF |mainlabel=- |headers=hide |intro= /  |?NumberDec#- }}) bits 5:0

ULA shadow screen from Bank 7 has higher priority than Timex modes, setting bit 6 to "1" together with one of the extended Timex graphic modes will result into classic ZX128 ULA mode using Bank 7 data.