EM78P258N
8-Bit Microprocessor with OTP ROM
6.1.6 R5 ~ R6 (Port 5 ~ Port 6)
R5 & R6 are I/O registers
The upper 2 bits of R5 are fixed to “0”
Only the lower 6 bits of R5 are available
The Bit2 ~ Bit5 of R6 are fixed to”0”
Only Bits 1, 2, 6 and, 7 of R6 are available
6.1.7 R7 (Port 7)
Bit
7
6
5
4
3
‘0’
2
‘0’
1
0
EM78P258N
ICE259N
‘0’
C3
‘0’
C2
‘0’
C1
‘0’
C0
‘0’
‘0’
I/O
I/O
RCM1
RCM0
NOTE
ꢀ
ꢀ
R7 is I/O registers
With EM78P258N, only the lower 1 bit of R7 is available.
Bit 7 ~ Bit 2:
[With EM78P258N]:
Unimplemented, read as ‘0’.
[With Simulator (C3~C0, RCM1, & RCM0)]: are IRC calibration bits in IRC oscillator
mode. Under IRC oscillator mode of ICE255N (with ICE259N)
(simulator, these are the IRC mode selection bits and IRC
calibration bits.
Bit 7 ~ Bit 4 (C3 ~ C0): Calibrator of internal RC mode
C3
C2
C1
C0
Frequency (MHz)
0
0
0
0
0
0
0
0
1
1
1
1
1
1
1
1
0
0
0
0
1
1
1
1
1
1
1
1
0
0
0
0
0
0
1
1
0
0
1
1
1
1
0
0
1
1
0
0
0
1
0
1
0
1
0
1
1
0
1
0
1
0
1
0
(1-36%) x F
(1-31.5%) x F
(1-27%) x F
(1-22.5%) x F
(1-18%) x F
(1-13.5%) x F
(1-9%) x F
(1-4.5%) x F
F (default)
(1+4.5%) x F
(1+9%) x F
(1+135%) x F
(1+18%) x F
(1+22.5%) x F
(1+27%) x F
(1+31.5%) x F
NOTE: 1. Frequency values shown are theoretical and taken from an instance of a
high frequency mode. Hence, they are shown for reference only. Definite
values will depend on the actual process.
2. Similar way of calculation is also applicable to low frequency mode.
Product Specification (V1.0) 06.16.2005
• 9
(This specification is subject to change without further notice)
ELAN [ ELAN MICROELECTRONICS CORP ]
