em78p809n ELAN Microelectronics Corp, em78p809n Datasheet - Page 62

• Manufacturer Part Number: em78p809n
• Description: 8-bit Microcontroller
• Manufacturer: ELAN Microelectronics Corp

EM78P809N
8-Bit Microcontroller
58 •
4.17 Code Option Register
4.17.1 Code Option Register (Word 0)
Table13. RC Oscillator Frequencies
Note: 1. Measured on DIP packages.
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:
Bit 12 ~ 9
100 pF
300 pF
20 pF
Cext
Bit 12 ~ 9 : Not used
Bit 8 (CLKS) : Instruction period option bit.
Refer to the Instruction Set section.
Bit 7 (ENWDTB) : Watchdog timer enable bit.
Bit 12~Bit 0
2. For design reference only.
Word 0
CLKS = “0” : two oscillator periods.
CLKS = “1” : four oscillator periods.
ENWDTB = “0” : Enable
ENWDTB = “1” : Disable
CLKS
Bit 8
ENWDTB
Rext
100k
100k
100k
Bit 7
3.3k
5.1k
3.3k
5.1k
3.3k
5.1k
10k
10k
10k
Bit 12~Bit 0
CYES
Word 1
Bit 6
(This specification is subject to change without further notice)
Average Fosc 5V, 25 ° C Average Fosc 3V, 25 ° C
Word 0
Bit 5
-
4.32 MHz
2.83 MHz
1.62 MHz
1.39 MHz
184kHz
950kHz
500kHz
580kHz
390kHz
200kHz
54kHz
21kHz
Product Specification (V1.0) 07.26.2005
Bit 4
OSC
Bit 3
HLP
Bit 12~Bit 0
Bit 2
PR2
Word 2
3.56 MHz
1.57 MHz
1.35 MHz
2.8 MHz
187kHz
930kHz
490kHz
550kHz
380kHz
200kHz
55kHz
21kHz
Bit 1
PR1
Bit 0
PR0