HD404356 Datasheet, PDF (70/100 Pages) Hitachi Semiconductor – 4-bit HMCS400-Series microcomputer

HD404358 Series
Serial data register (upper digit) (SRU: $007)
Bit
Initial value
Read/Write
Bit name
3
2
1
0
Undefined Undefined Undefined Undefined
R/W
R/W
R/W
R/W
SR7
SR6
SR5
SR4
Figure 58 Serial Data Register (SRU)
Transmit clock
Serial output
data
1
2
3
4
5
6
7
8
LSB
MSB
Serial input data
latch timing
Figure 59 Serial Interface Output Timing
Port Mode Register A (PMRA: $004): This register has the following functions (figure 60).
• R0₁/SI pin function selection
• R0₂/SO pin function selection
Port mode register A (PMRA: $004) is a 4-bit write-only register, and is reset to $0 by MCU reset.
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