Epson S1C63558 4.14 Telephone Function (Tone/Pulse Dialer), 4.14.1 Configuration of tone/pulse dialer

CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (Telephone Function)

4.14 Telephone Function (Tone/Pulse Dialer)

4.14.1 Configuration of tone/pulse dialer

The S1C63558 has a telephone function built-in. This function includes DTMF (Dual Tone Multi-Fre- quency), DP (Dialing pulse), Pause, Flash, Hold-line, Mute control, Hook switch control and Handfree control.

The configuration of the telephone function is shown in Figure 4.14.1.1.

HS (Kxx)

CPU

Data bus

3.58 MHz	Frequency	DTMF
oscillator	divider			TONE
		generator
Control		DP		DP
registers		generator
		Telephone	R12, R13	HFO (R13)
32 kHz	Frequency	timing
			registers	HDO (R12)
oscillator	divider	generator
Interrupt		Mute		XRMUTE (R11)
		generator
circuit				XTMUTE (R10)

Fig. 4.14.1.1 Configuration of tone/pulse dialer

This dialer has built-in a DTMF generator for generating tones and a DP generator for generating dial pulses.

Either DTMF mode or DP mode can be selected by software.

In the DTMF mode, the DTMF generator uses the OSC3 (3.58 MHz) clock to generate the tone signal set by software (signal tone or dual tone) and outputs it to the TONE terminal.

In the DP mode, the DP generator uses the OSC1 (32 kHz) clock to generate the dial pulses for the number set by software to the DP terminal.

The push button matrix is configured using the input and output ports. The hook switch should be connected to an input port. The hook switch can be controlled by software, this makes it possible to start calling even if the telephone is on-hook.

Besides the above terminals, The R10 to R13 terminals can be used as an XTMUTE (transmitter mute signal output), XRMUTE (receiver mute signal output), HDO (hold line signal output) and HFO (hand free signal output). These terminal functions can be configured by software. (See Section 4.5, "Output Port".)

This dialer has a built-in interrupt circuit that can generate an interrupt when execution of a dial signal output, a pause function or a flash function is completed.

112 EPSON S1C63558 TECHNICAL MANUAL