Keyboard: Difference between revisions

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|PortMask=%xxxx xxxx ---- ---0 where only one bit in x is 0
|PortMask=%xxxx xxxx ---- ---0 where only one bit in x is 0
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Reads keys on the keyboard depending on the upper byte of the port number.
Reads keys on the keyboard depending on the upper byte of the port number. The five keys are represented by bits 0-4 of the read byte, listed below with bit 4 first down to bit 0. A zero means that the key is pressed.


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Revision as of 15:56, 29 August 2017

Number PortNumber::$**FE
Decimal NumberDec::
Short desc. ShortDesc::Series of specific ports that read keyboard key presses.
Bit Mask PortMask::%xxxx xxxx ---- ---0 where only one bit in x is 0
Readable Readable::Yes
Writable Writable::No
Subsystem Subsystem::Input

Reads keys on the keyboard depending on the upper byte of the port number. The five keys are represented by bits 0-4 of the read byte, listed below with bit 4 first down to bit 0. A zero means that the key is pressed.

Port upper byte Keys affected
$7F B, N, M, Symbol Shift, Space
$BF H, K, J, L, Enter
$DF Y, U, I, O P
$EF 6, 7, 8, 9, 0
$F7 5, 4, 3, 2, 1
$FB T, R, E, W, Q
$FD G, F, D, S, A
$FE V, C, X, Z, Caps Shift

File:Speckeys.png