EM78P809N

8-Bit Microcontroller

Table13. RC Oscillator Frequencies

Cext

Rext

Average Fosc 5V, 25°C

Average Fosc 3V, 25°C

 

 

 

 

 

3.3k

4.32 MHz

3.56 MHz

 

 

 

 

20 pF

5.1k

2.83 MHz

2.8 MHz

 

 

 

10k

1.62 MHz

1.57 MHz

 

 

 

 

 

 

100k

184kHz

187kHz

 

 

 

 

 

3.3k

1.39 MHz

1.35 MHz

 

 

 

 

100 pF

5.1k

950kHz

930kHz

 

 

 

10k

500kHz

490kHz

 

 

 

 

 

 

100k

54kHz

55kHz

 

 

 

 

 

3.3k

580kHz

550kHz

 

 

 

 

300 pF

5.1k

390kHz

380kHz

 

 

 

10k

200kHz

200kHz

 

 

 

 

 

 

100k

21kHz

21kHz

 

 

 

 

Note: 1. Measured on DIP packages.

2.For design reference only.

4.17Code Option Register

The EM78P809N has one CODE option word that is not part of the normal program memory. The option bits cannot be accessed during normal program execution.

Code Option Register and Customer ID Register arrangement distribution:

Word 0

Word 1

Word 2

 

 

 

Bit 12~Bit 0

Bit 12~Bit 0

Bit 12~Bit 0

 

 

 

4.17.1 Code Option Register (Word 0)

 

 

Word 0

Bit 12 ~ 9 Bit 8

Bit 7

Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0

CLKS ENWDTB CYES

-

OSC HLP PR2 PR1 PR0

Bit 12 ~ 9 : Not used

Bit 8 (CLKS) : Instruction period option bit.

CLKS = “0” : two oscillator periods.

CLKS = “1” : four oscillator periods.

Refer to the Instruction Set section.

Bit 7 (ENWDTB) : Watchdog timer enable bit.

ENWDTB = “0” : Enable

ENWDTB = “1” : Disable

58

Product Specification (V1.0) 07.26.2005

(This specification is subject to change without further notice)

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Image 62
IBM EM78P809N manual Code Option Register Word, For design reference only, Bit 12 ~ 9 Not used