IBM EM78P447N Network Card User Manual


 
EM78P447N
8-Bit Microcontroller with OTP ROM
Product Specification (V1.1) 03.30.2005
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(This specification is subject to change without further notice)
Bit 8 (CLKS): Instruction period option bit.
0: two oscillator periods.
1: four oscillator periods.
Refer to the section on Instruction Set.
Bit 7(ENWDTB): Watchdog timer enable bit.
0: Enable
1: Disable
Bit 6: Type selection for EM78P447NA or EM78P447NB
0: EM78P447NB
1: EM78P447NA
Bit 5 (HLF): XTAL frequency selection
0: XTAL2 type (low frequency, 32.768KHz)
1: XTAL1 type (high frequency)
This bit will affect system oscillation only when Bit4 (OSC) is “1”. When OSC is”0”, HLF
must be “0”.
NOTE
The transient point of system frequency between HXT and LXY is around 400 KHz.
Bit 4 (OSC): Oscillator type selection.
0:RC type
1:XTAL type (XTAL1 and XTAL2)
Bit 3 (HLP): Power selection.
0: Low power
1: High power
Bit 2~0 (PR2~PR0): Protect Bit
PR2~PR0 are protect bits, protect type as following
PR2 PR1 PR0 Protect
0 0 0 Enable
0 0 1 Enable
0 1 0 Enable
0 1 1 Enable
1 0 0 Enable
1 0 1 Enable
1 1 0 Enable
1 1 1 Disable