CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (Telephone Function)

PAUSE: Pause function (FF14H•D1)

Executes the pause function.

When "1" is written: Execute pause function

When "0" is written: Cancel pause function

Reading: Always "0"

Writing "1" to PAUSE executes the pause function. The pause time set by the PTS register is inserted to the DP output signal. An interrupt occurs when the pause is released and the PAUSE bit is automatically cleared to "0".

This bit is write-only, and so is always "0" at reading.

FLASH: Flash function (FF14H•D0)

Executes the flash function.

When "1" is written: Execute flash function

When "0" is written: Cancel flash function

Reading: Always "0"

Writing "1" to FLASH executes the flash function. The DP, XRMUTE (R11) and XTMUTE (R10) terminals go Low (VSS) level during the flash period set by the FTS register and then an interrupt occurs. At the same time the FLASH bit is automatically cleared to "0" by the interrupt.

This bit is write-only, and so is always "0" at reading.

HF: Handfree (FF14H•D3)

Controls the handfree function and HFO signal output.

When "1" is written: ON (High level output on R13 terminal)

When "0" is written: OFF (Low level output on R13 terminal)

Reading: Valid

This register controls the HFO signal output to the R13 terminal when the HFO function has been se- lected. The HFO output function is set by writing "1" to the CHFO register (FF13H•D3). In this case, the R13 register must be fixed at "1" and the R13HIZ register at "0".

When "1" is written to the HF register, the HFO (R13) terminal goes High (VDD) level. When "0" is written, the HFO (R13) terminal goes Low (VSS) level.

At initial reset, this register is set to "0".

IDP0–IDP3: Inter-digit pause time selection (FF15H)

Select an inter-digit pause time for the pulse mode from among the 15 types shown in Table 4.14.10.4.

Table 4.14.10.4 Selection of inter-digit pause times

 

IDP

 

Inter-digit pause

D3

D2

D1

D0

time (msec)

0

0

0

0

Unavailable *

0

0

0

1

94

0

0

1

0

188

0

0

1

1

281

0

1

0

0

375

0

1

0

1

469

0

1

1

0

563

0

1

1

1

656

 

IDP

 

Inter-digit pause

D3

D2

D1

D0

time (msec)

1

0

0

0

750

1

0

0

1

844

1

0

1

0

938

1

0

1

1

1031

1

1

0

0

1125

1

1

0

1

1219

1

1

1

0

1313

1

1

1

1

1406

∗Do not write "0" (0000B) to the IDP register because it may cause a malfunction.

The specified inter-digit pause time will be inserted after each dialing pulse digit. This selection is valid only for pulse mode.

At initial reset, this register is set to "1000B" (750 msec).

S1C63558 TECHNICAL MANUAL

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