27963 Parallax Inc, 27963 Datasheet - Page 5

• Manufacturer Part Number: 27963
• Description: SOLUTIONS CUBED: MEMKEY
• Manufacturer: Parallax Inc

Specifications of 27963

• Accessory Type: Keypad Encoder
• Product: Microcontroller Accessories
• For Use With/related Products: BASIC Stamp®
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Miniature Engineering Modules – MEMKey
OPERATION
communicate via a serial interface or the standard
PC/AT interface. In addition, it is fully programmable.
Access to the programmable features is through the
serial protocol. If the device is to be used in the PC/AT
mode, it must first be programmed using the serial
mode and then put into PC/AT mode. Details for using
the MEMKey in the serial mode are given in the Serial
Operation subsection.
using the PC/AT mode see the subsection PC/AT
Operation.
Key Map
keypad into the following key map. The map shows
the physical key that corresponds to a particular
row/column intersection. For example, if the key at
row 3, column 2 was pressed down, the MEMKey
would decode that as physical key 14 being pressed
down.
Serial Operation
keypad encoder. The value that the MEMKey sends to
the host when a key is pressed can be individually
programmed for each key.
configured in any row and column configuration. This
allows for easy connections between the key matrix
and the encoder. The amount of time that keys are
debounced can be set.
enabled or disabled. In addition, the typematic delay
and rate can be programmed. Also, the MEMKey can
be configured to automatically report key presses. Or
it can store the key values in an 8 key buffer and
await a polling command from the host before it sends
its key data.
there
SOLUTIONS CUBED
530-891-8045
Column/
Row
0
1
2
3
4
The MEMKey is a keypad encoder which can
The MEMKey maps the rows and columns of the
Physical MEMKey key map
In serial mode the MEMKey is a fully configurable
0
0
4
8
12
16
The KEY pin toggles high whenever
1
1
5
9
13
17
For further information on
Typematic action can be
2
2
6
10
14
18
The KX pins can be
3
3
7
11
15
19
is
key data in the buffer. Using this KEY pin allows for
synchronization between the host and MEMKEY
during poll mode. In addition, the serial mode is used to
program the PC/AT key values, if they need to be
different than the pre-configured values.
Serial Default Settings
will work with no user setup necessary. The table
below shows the default values for the MEMKey.
Item
Key 0
Key 1
Key 2
Key 3
Key 4
Key 5
Key 6
Key 7
Key 8
Key 9
Key 10
Key 11
Key 12
Key 13
Key 14
Key 15
Key 16
Key 17
Key 18
Key 19
Pin K0
Pin K1
Pin K2
Pin K3
Pin K4
Pin K5
Pin K6
Pin K7
Pin K8
Debounce Delay
Typematic Delay
Typematic Rate
Typematic Operation
Automatic Operation
The MEMKey is pre-configured at the factory so it
Default settings
Value
‘00’H
‘01’H
‘02’H
‘03’H
‘04’H
‘05’H
‘06’H
‘07’H
‘08’H
‘09’H
‘0A’H
‘0B’H
‘0C’H
‘0D’H
‘0E’H
‘0F’H
‘10’H
‘11’H
‘12’H
‘13’H
Row 0
Row 1
Row 2
Row 3
Column 0
Column 1
Column 2
Column 3
Row 4
10mS
500mS
1 per 100mS
On
On
4