GMS84512 Datasheet, PDF (54/123 Pages) Hynix Semiconductor – 8-BIT SINGLE CHIP MICROCOMPUTER

GMS 84512 / 84524
3.5.2 Serial I/O Mode Register
This register controls serial function. According to SCK1, SCK0 internal clock or external clock
can be used.
SERIAL I/O MODE REGISTER
SIOM
<00D6_H>
-
R/W R/W R/W R/W R/W R/W
R
7
6
5
4
3
2
1
0
- IOSW SM1 SM0 SCK1 SCK0 SIOST SIOSF
Initial value when MCU Reset
[ -000 0001 ]
Serial Input Selection
0 : Via Sin
1 : Via Sout
Serial Operation Mode
01 : Sending Mode (Sclk, Sout)
10 : Receiving Mode (Sclk, Sin)
Others : Selection of R33,R34,R35
Serial Transmission status FLAG
0 : Serial during transmission
1 : Serial finished
Serial Transmission Start
0 : Invalid
1 : Start(After one SCK, becomes”0”)
Serial Transmission Clock Selection
00 : PS3 ( 1uS )
01 : PS4 ( 2uS )
10 : PS5 ( 4uS )
11 : External Clock
l Port Selection According to Serial I/O Mode
SM1
0
0
1
1
SM0
0
1
0
1
Function Selection
-
Sending Mode
Receiving Mode
-
R33/ Sout
R33
Sout
R33
R33
Port Selection
R34/ Sclk
R34
Sclk
Sclk
R34
R35/ Sin/ Cin3 *
R35
R35
Sin
R35
* If Cin3 is used as A/D comparator input channel, R35 port do not operate as output..
l Selection of Serial input pin with the IOSW
When receiving mode, serial input pin is selected by IOSW. That, if IOSW=0, R35/Sin is
selected. If IOSW=1, R33/Sout
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