Table 2: Digits vs. input data vs. tone output frequency (parallel mode)

Digit

D3

D2

D1

D0

Tone Output

Frequency (Hz)

10001

697

+1209

20010

697

+1336

30011

697

+1477

40100

770

+1209

50101

770

+1336

60110

770

+1477

70111

852

+1209

81000

852

+1336

91001

852

+1477

01010

941

+1336

*

1011

941

+1209

#

1100

941

+1477

A

1101

697

+1633

B

1110

770

+1633

C

1111

852

+1633

D

0000

941

+1633

HT9200A/HT9200B

Rev. 1.50

6

April 29, 2013

For the HT9200B, the S/P pin has to be connected low for

serial mode operation.

Parallel mode ( HT9200B)

The HT9200B provides four data inputs D0~D3 to gener-

ate their corresponding DTMF signals. The S/P has to be

connected high to select the parallel operation mode.

Then the input data codes should be determined. Finally,

the CE is connected low to transmit the DTMF signal from

the DTMF pin.

ing edge to the DTMF signal output.

The relationship between the digital codes and the tone

output frequency is illustrated in Table 2. As for the control

timing diagram, see Figure 2.

When the system is operating in the parallel mode,

D0~D3 are all in the floating state. Thus, these data in-

put pins should not float.

C E

S / P

X 2

D A T A

C L K

L S B

M S B

D T M F

L S B

M S B

L S B

M S B

1

1

1

1

1

D i g i t 1

D i g i t 2

D i g i t 1

D T M F s i g n a l

D i g i t 2

D T M F s i g n a l

S t o p c o d e

( O s c i l l a t o r )

Figure 1