–

–

–

–

6

7

The Encoder Board

The encoder board has two sections that are of primary interest: the

encoder area and the transmitter area.

The Encoder Area

Figure 5 shows the encoder area of the development board.

The encoder is placed in the center beneath the Linx logo. To the right are

buttons that pull the encoder data lines high when pressed. Button S0

corresponds to data line D0, S1 to D1 and so forth.

The diodes to the left isolate the data lines from each other while allowing

any line to activate the SEND line.

Beneath the encoder are two LEDs. D12 is connected to the MODE_IND

line and lights up as described in the MS Encoder Data Guide. D8 is

connected to the TX_CNTL line and provides visual feedback by lighting up

when the encoder sends a word.

Beneath the LEDs is a button that is connected to the CREATE line. This

button is used to create the Address and set the Control Permissions as

described in the MS Series Encoder Data Guide.

There are three function switches to the left of the CREATE button. BSEL0

and BSEL1 are used to set the baud rate of the encoder as described

in Figure 6. The maximum baud rate for the LR Series is 10,000bps, so

only 2,400 and 9,600bps can be used on boards populated with these

modules. The ES Series can use all four baud rates.

Figure 5: The Encoder Area

The PDN switch connects the TX_CNTL line of the encoder to the PDN

line of the transmitter so that the TX Control Mode of the encoder can be

tested. This mode is described in the MS Series Encoder Data Guide.

If a BSEL switch is up, then the line is high (1, VCC); if down, then the line

is low (0, GND). If the PDN switch is up, then the encoder’s TX_CNTL line

is connected to the transmitter’s PDN line; if down, it is not connected and

the LR Series transmitter is not activated unless its PDN line is pulled high

externally. The ES Series transmitter has an internal pull-up, so is active

unless pulled low.

Baud Rate Selection Table

SEL_BAUD1

SEL_BAUD0

Baud Rate (bps)

0

0

2,400

0

1

9,600

1

0

19,200

1

1

28,800

Figure 6: Baud Rate Selection Table

for the signal to be received correctly. The maximum baud rate for the

LR Series is 10,000bps, so only 2,400 and 9,600bps can be used on

boards populated with these modules. The ES Series transmitter can

use all four baud rates. If the switch is up, then the line is high, if it is

down, then the line is low.