H8S2194 Datasheet, PDF (650/1078 Pages) Renesas Technology Corp – Renesas 16-Bit Single-Chip Microcomputer

Section 28 Servo Circuits
(2) Servo Control Register (SPCR)
Bit :
7
6
5
4
3
2
1
0
—
—
—
SPCR4 SPCR3 SPCR2 SPCR1 SPCR0
Initial value :
1
1
1
0
0
0
0
0
R/W : —
—
—
W
W
W
W
W
Controls input and output of each pin (PS4 to PS0) for each bit when the servo port/general-
purpose port dual-purpose pin is used as the general-purpose port. If SPCR is set to 1, the
corresponding PS4 to PS0 pins function as output pins; if cleared to 0, they function as input pins.
Settings of SPCR and SPDR are valid if the corresponding pins are set to general-purpose I/O by
SPMR.
SPCR is an 8-bit write-only register. If read is attempted, an undetermined value is read out.
Bits 7 to 5 are reserved bits. Writes are disabled.
SPCR is initialized to H'E0 by a reset or stand-by.
Bit n
SPCRn
0
1
Description
PSn pin functions as input
PSn pin functions as output
(Initial value)
(3) Servo Data Register (SPDR)
Bit :
7
6
5
4
3
2
1
0
—
—
—
SPDR4 SPDR3 SPDR2 SPDR1 SPDR0
Initial value :
1
1
1
0
0
0
0
0
R/W : —
—
—
R/W
R/W
R/W
R/W
R/W
Stores the data of each pin (PS4 to PS0) when the servo port/general-purpose dual-purpose pin is
used as general-purpose port. If the port is accessed for read when SPCR is 1 (output), the SPDRn
value is read directly. Accordingly, this register is not affected by the state of the pin. If the port is
accessed for read when SPCR is 0 (input), the state of the pin is read out.
SPDR is an 8-bit read/write register. Bits 7 to 5 are reserved. No write in it is valid. If read is
attempted, an undetermined value is read out.
SPCR is initialized to H'E0 by reset or stand-by.
Rev.3.00 Jan. 10, 2007 page 614 of 1038
REJ09B0328-0300