www.clare.com

4

M-986-2A1

Rev. 3

2 of 6 Coding Format

Byte

Bit 7

Bit 6

Bit 5

Bit 4

Bit 3

Bit 2

Bit 1

Bit 0

Transmit tone command

1

CHN

F6

F5

F4

F3F2

F1

Receive tone return

0

CHN

F6

F5

F4

F3F2

F1

CHN: 1 = channel 2;

0 = channel 1

R1 MF Frequencies:

Bit name

Frequency (Hz)

Bit name

Frequency (Hz)

F6

1700

F3

1100

F5

1500

F2

900

F4

1300

F1

700

(5) Data is driven onto D7-D0 by the M-986 until the

RD signal is driven high by the host processor.

Clock Characteristics and Timing

Internal Clock Option: The internal oscillator is enabled

by connecting a crystal across X1 and X2/CLKIN. The

frequency of CLKOUT is one-fourth the crystal funda-

mental frequency. The crystal should be 20.48 MHz,

fundamental mode, and parallel resonant, with an

effective series resistance of 30 ohms, a power dissi-

pation of 1 mW, and be specified at a load capacitance

of 20 pF.

External Clock Option: An external frequency source

can be used by injecting the frequency directly in

X2/CLKIN with X1 left unconnected. The external fre-

quency injected must conform to the specifications list-

ed in External Frequency Specifications table on page

6.

Flammability/Reliability Specifications

Reliability:

185 FITS failures/billion hours

Flammability:

Passes UL 94 V-0 tests

Binary Coding Format

Byte

Bit 7

Bit 6

Bit 5

Bit 4

Bit 3

Bit 2

Bit 1

Bit 0

Transmit tone command

1

CHN

0

0

A

B

C

D

Receive tone return

0

CHN

0

0

A

B

C

D

CHN: 1 = channel 2;

0 = channel 1

R1 MF Frequencies:

ABCD

Frequencies (Hz)

Name

ABCD

Frequencies (Hz)

Name

0 0 0 0

Tone off

-

1 0 0 0

900 & 1500

Digit 8

0 0 0 1

700 & 900

Digit 1

1 0 0 1

1100 & 1500

Digit 9

0 0 1 0

700 & 1100

Digit 2

1 0 1 0

1300 & 1500

Digit 0

0 0 1 1

900 & 1100

Digit 3

1 0 1 1

700 & 1700

ST3

0 1 0 0

700 & 1300

Digit 4

1 1 0 0

900 & 1700

ST1

0 1 0 1

900 & 1300

Digit 5

1 1 0 1

1100 & 1700

KP

0 1 1 0

1100 & 1300

Digit 6

1 1 1 0

1300 & 1700

ST2

0 1 1 1

700 & 1500

Digit 7

1 1 1 1

1500 & 1700

ST