HT95L100/10P

Rev. 0.10

24

October 1, 2002

Preliminary

PFD generator

Register

Label

Bits

R/W

Function

PFDC

(2EH)

¾

3~0

RO

Unused bit, read as

²0²

PFDEN

4

RW

1: Enable PFD output

0: Disable PFD output, the MUSIC pin output low level.

PRES0

PRES1

5

6

RW

Bit6, 5=00: Prescaler output= PFD frequency source/1

Bit6, 5=01: Prescaler output= PFD frequency source/2

Bit6, 5=10: Prescaler output= PFD frequency source/4

Bit6, 5=11: Prescaler output= PFD frequency source/8

FPFD

7

RW

1: The PFD frequency source is 3.58MHz/4

0: The PFD frequency source is 32768Hz

PFDD

(2FH)

¾

7~0

RW

PFD data register

The PFD (programmable frequency divider) is implemented in the phone controller. It is composed of two portions: a

prescaler and a general counter.

The prescaler is controlled by the register bits, PRES0 and PRES1. The general counter is programmed by an 8-bit

register PFDD.

The source for this generator can be selected from 3.58MHz/4 or 32768Hz. To enable the PFD output, write 1 to the

PFDEN bit.

The PFDD is inhibited to write while the PFD is disabled. To modify the PFDD contents, the PFD must be enabled.

When the generator is disabled, the PFDD is cleared by hardware.

PFD output frequency=

Prescaler output

2(N

1)

´+

, where N=the value of the PFDD

Mask option table

The following shows many kinds of mask options in the telephone controller. All these options should be defined in or-

der to ensure proper system functions.

Name

Mask Option

WDT

WDT source selection

RC

®Select the WDT OSC to be the WDT source.

T1

®Select the instruction clock to be the WDT source.

32kHz

®Select the external 32768Hz to be the WDT source.

Disable

®Disable WDT function.

WDTinstr

This option defines how to clear the WDT by instruction.

One clear instruction

®The ²CLR WDT² can clear the WDT.

Two clear instructions

®Only when both of the ²CLR WDT1² and ²CLR WDT2² have been

executed, then WDT can be cleared.

Wake-up PA

Port A wake-up selection.

Define the activity of wake-up function.

All port A have the capability to wake-up the chip from a HALT.

This wake-up function is selected per bit.

Pull-high Port A

Pull-high Port B

Pull-high Port E

Pull-high option.

This option determines whether the pull-high resistance is viable or not.

Port A pull-high option is selected per bit.

Port B pull-high option is selected per bit.

Port E pull-high option is selected per nibble.

P r e s c a l e r

P r e s c a l e r

O u t p u t

P . D D

P R E S 1 , P R E S 0

3 2 7 6 8 H z

3 . 5 8 M H z / 4

P . D E N

P . D

O u t p u t

M U S I C