Mitsubishi Electric Apricot LS Pro, Техническое описание оборудования

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Chapter 4
Chapter 6
Chapter 4
Peripheral items
Appendix A
Appendix C
Pr
eface
Chapter 4
LS PRO HARDWARE TECHNICAL REFERENCE 4/21
Buffer overflow (00h or FFh)
This code is sent to the system unit when the type ahead buffer overflows. 00h is sent
if code sets 2 or 3 are in use; FFh is sent if code set 1 is in use.
Identification byte (83ABh)
These bytes are sent to the system unit in response to a read ID command. The
keyboard stops scanning, sends the ID bytes, then continues scanning. The least
significant byte is sent first.
Commands from Commands are sent from the system unit to the keyboard via the keyboard controller
the system unit data buffer. The controller inserts a parity bit and transmits the data serially to the
keyboard. No further transmission is sent to the keyboard until the keyboard
acknowledges receipt of the data byte.
The command bytes which the keyboard recognises are listed below.
Command Description
EDh Set/reset LED indicators
EEh Echo
EFh No operation
F0h Select alternate scan codes
F1h No operation
F2h Read ID
F3h Set typematic rate/delay
F4h Enable
F5h Default disable
F6h Set default
F7h Set all keys typematic
F8h Set all keys make/break
F9h Set all keys make only
FAh Set all keys typematic/make/break
FBh Set key to typematic
FCh Set key to make/break
FEh Resend
FFh Reset
When the keyboard receives any of these commands, it sends an ACKnowledge (FAh)
response. If the data is incorrectly received the keyboard sends a RESEND (FEh)
request.
The use and formats of these commands is described in the following paragraphs.