EM78P809N
8-Bit Microcontroller
Table13. RC Oscillator Frequencies
Cext
Rext
3.3k
5.1k
10k
Average Fosc 5V, 25°C Average Fosc 3V, 25°C
4.32 MHz
2.83 MHz
1.62 MHz
184kHz
1.39 MHz
950kHz
500kHz
54kHz
3.56 MHz
2.8 MHz
1.57 MHz
187kHz
1.35 MHz
930kHz
490kHz
55kHz
20 pF
100 pF
300 pF
100k
3.3k
5.1k
10k
100k
3.3k
5.1k
10k
580kHz
390kHz
200kHz
21kHz
550kHz
380kHz
200kHz
21kHz
100k
Note: 1. Measured on DIP packages.
2. For design reference only.
4.17 Code 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
PR1
Bit 0
CLKS
ENWDTB CYES
-
OSC
HLP
PR2
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)
ELAN [ ELAN MICROELECTRONICS CORP ]
