8

6399A–DRMSD–13-Oct-08

ATSAM2553

The following signals are controlled by firmware, therefore their timing relationships is deter-

mined by firmware only.

Table 4-4.

Keyboard, Switches, LEDs, Sliders, Scanning

Pin Name

Pin#

Type

Function

KBDIO

19

OUT

If 1 BR[0-10] & MK[0-10] hold keyboard contact input data. If 0

BR[0-10] holds switch status input, MK[0-10] holds led data

output.

ROW0-ROW3

56-59

OUT

Row select: keyboard, switches/LEDs, external slider analog

multiplexer (4051) channel select. Sixteen rows combined

with eleven BR/MK columns allow to control 176 keys, 176

switches, 88 leds and 16 sliders. The programmable bit P0

can be programmed to be used as ROW4. This allows to use

keyboards with matrix other than 8*11 (e.g. 22*4) or multiple

keyboards up to 264 keys.

BR0-BR10

104-114

IN 5VT

Kbd contact 1/switch status. When KBDIO =1 then BR[0-10]

holds the keyboard key-off or first contact status. This can be

configured as normally close (spring type), normally open

(rubber type), common anode or common cathode contact

diodes. When KBDIO = 0 then BR[0-10] holds the switch

status from ROW[0-4].

MK0-MK10

79-83,86-91

I/O 5VT

Kbd contact 2/LED data. When KBDIO = 1 then MK[0-10]

holds the keyboard key-on or second contact status. This can

be configured as common anode or common cathode contact

diodes. When KBDIO = 0 then MK[0-10] holds the LED data

from ROW[0-4]

VIN

15

ANA

Slider analog input. Ranges from AGND to VA33. Should hold

the ROW[0-3] slider voltage. Multiple sliders should be

connected through external analog multiplexer(s) like 4051.

Table 4-5.

LCD Display Interface

Pin Name

Pin#

Type

Function

RS

5

OUT

Select Instruction (LOW) or Data (HIGH)

RW

4

OUT

Select Write (LOW) or Read (HIGH)

ENB

3

OUT

Enable, active high

DB0-DB7

6-13

I/O 5VT

Bi-directional data bus