PixArt Imaging Inc.

PAC107

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42

PixArt Imaging Inc.

E-mail:

fae_service@pixart.com.tw

V1.4, Aug, 2005

RCLK

Bit

TCLCK

Bit

Receiver

Baud Rate Generator

Transmitter

Baud Rate generator

0

0

Timer 1

Timer 1

0

1

Timer 1

Timer 2

1

0

Timer 2

Timer 1

1

1

Timer 2

Timer 2

Note: Timer 2 advanced for every state time (2Tosc) when it is in the baud rate generator

mode. In the baud rate formula that follows, “RCAP2H,RCAP2L” denotes the contents of

RCAP2H and RCAP2L taken as a 16-bit unsigned integer:

NOTE

: When timer 2 is configured as a timer and is in baud rate generator mode, do not

read or write the TH2 or TL2 registers. The timer is being incremented every state time,

and the result of a read or write may not be accurate. In addition, you may read, but not

write to, the RCAP2 registers; a write may overlap a reload and cause write and/or reload

errors.

XTAL1

TR2

T2

0

1

2

C/ T2

Timer 2 in Baud Rate Generator Mode

TL2

(8 Bits)

TH2

(8

Bits)

RCAP2H

RCAP2L

2

0

1

Timer 1

Overflow

SMOD

0

1

TCLCK

Interrup

t

Request

EXF2

EXEN2

T2EX

16

TX

Clock

NOTE:

Oscillator frequency

is divided by 2, not 12.

Note availability of additional external interrupt

0

1

RCLCK

16

RX

Clock

0

1

SMOD1

16

TX1

Clock

16

RX1

Clock

Fosc

32 X [65536 - (RCAP2H,RACAP2L)]

Sreial I/O Mode 1 and 3 Baud Rate