em78f644nso28s ELAN Microelectronics Corp, em78f644nso28s Datasheet - Page 166

• Manufacturer Part Number: em78f644nso28s
• Description: Flash Series 8-bit Microcontroller
• Manufacturer: ELAN Microelectronics Corp

EM78F648/644/642/641/548/544/542/541N
8-Bit Microcontroller
156 •
6.19 Code Option Register
The EM78F648/644/642/641/548/544/542/541N has a Code Option Word that is not
part of the normal program memory. The option bits cannot be accessed during
normal program execution.
Their respecrtive Code Option Register and Customer ID Register arrangement
distribution are as follows:
6.19.1 Code Option Register (Word 0)
6.19.1.1 EM78F644/642/641/544/542/541N Code Option Word 0
Bit 12:
Bit 11 (NRHL): Noise Rejection High/Low Pulse Define bit. INT pin is a falling edge
Bit 10 (NRE):
Bit 9 (RESETENB): Reset Pin Enable Bit
Bit 12 Bit 11 Bit 10 Bit 9
EM78F644/642/641/544/542/541N
EM78F648/548N
-
Bit 12~Bit 0
Bit 14~Bit 0
NRHL
Word 0
Word 0
The noise rejection function is turned off in the LXT2 and in Sleep mode.
NRE
The “RESETENB” bit is NOT available from EM78F644/544N
Not used, set to “0” all the time
trigger.
0: Pulses equal to 32/fc [s] is regarded as signal (default)
1: Pulses equal to 8/fc [s] is regarded as signal
Noise Rejection Enable bit. INT pin is a falling edge trigger.
0: Enable noise rejection (default)
1: Disable noise rejection
Note that in Low Crystal oscillator (LXT2) mode, the noise rejection
circuit is always disabled
0: P83 set to I/O pin (default)
1: P83 set to /RESET pin
RESET
ENB
CLKS1 CLKS0
Bit 8
Bit 12~Bit 0
Bit 14~Bit 0
Word 1
Word 1
Bit 7
(This specification is subject to change without further notice)
Word 0
NOTE
NOTE
WDTB
Bit 6
EN
Product Specification (V1.0) 05.05.2010
OSC2 OSC1 OSC0
Bit 5
Bit 12~Bit 0
Bit 14~Bit 0
Word 2
Word 2
Bit 4
Bit 3 Bit 2 Bit 1 Bit 0
Protect