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7.5.2.2

Special

Considerations

Regarding

Down/Up

Mode

--

If

two

DOWN/UP

keys

are

released

simultaneously

(within

the

same

scan),

and

there

are

no

other

DOWN/UP

keys

down

on

the

keyboard,

only

one

ALL

UPS

code

is

generated.

7.5.2.3

Autorepeat

Rates

There

are

four

buffers

in

the

keyboard

to

store

autorepeat

rates.

They

are

numbered

zero

through

three.

Each

buffer

stores

the

following

two

values.

These

values

can

be

changed

by

the

system

module.

The

timeout

value

The

interval

value

The

timeout

value

is

the

amount

of

time

between

the

detection

of

a

down

key

and

the

transmission

of

the

first

metronome

code

(defaults

range

from

300

to

500

ms).

The

interval

value

is

the

number

of

metronome

codes

per

second

(defaults

to

30).

Each

division

is

associated

with

one

of

the

four

buffers.

Rates

are

taken

from

the

associated

buffer

each

time

the

autorepeat

timers

are

loaded.

This

buffer-to-division

association

can

be

changed

by

the

system

module,

or

left

to

default.

7.5.3

Keyboard

Peripherals

This

section

describes

the

peripherals

The

keyclick,

bell,

and

LEOs

are

peripherals.

Refer

to

section

7.5.5.3

module

control

over

these

peripherals.

available

on

the

keyboard.

all

considered

keyboard

for

information

on

system

7.5.3.1

Audio

The

keyclick

is

a 2 rns

beep

and

the

bell

is

a

125

ms

beep.

The

bell

is

sounded

only

upon

request

from

the

system

module.

The

keyclick

(if

not

disabled

by

the

system

module)

sounds

when

a

key

is

pressed,

when

a

metronome

code

is

sent,

or

when

the

system

module

receives

a

sound

keyclick

command.

If

either

the

BI1

or

B99

keys

(the

left

and

right

SHIFT

keys

on

the

LK20l)

or

the

C99

key

(the

CTRL

key

on

the

LK20l)

are

pressed,

the

keyclick

is

not

generated.

However,

if

a command

is

sent

from

the

system

module

to

enable

the

keyclick

on

the

C99

key,

the

keyclick

is

generated

(refer

to

section

7.5.5.3).

Figure

7-7

shows

the

positions

of

these

keys.

The

keyclick

or

bell

{or

both)

may

be

disabled.

When

the

keyclick

or

bell

is

disabled,

it

does

not

sound.

If

the

system

module

requests

sound

(refer

to

section

7.5.5.3)

the

keyclick

or

the

bell

does

not

sound.

7-25

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