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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
A
B
C
D
Receive tone return
0
CHN
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