HYUNDAI MicroElectronics
GMS81C2012/GMS81C2020
14. SERIAL PERIPHERAL INTERFACE
The Serial Peripheral Interface (SPI) module is a serial in-
terface useful for communicating with other peripheral of
microcontroller devices. These peripheral devices may be
serial EEPROMs, shift registers, display drivers, A/D con-
verters, etc. The Serial Peripheral Interface(SPI) is 8-bit
clock synchronous type and consists of serial I/O register,
serial I/O mode register, clock selection circuit octal
counter and control circuit. The SOUT pin is designed to
input and output. So Serial Peripheral Interface(SPI) can
be operated with minimum two pin
SIOSF
SIOST
Start
SCK[1:0]
POL
Complete
overflow
4
÷
÷
00
01
XIN PIN
SPI
CONTROL
CIRCUIT
16
“0”
“1”
Clock
Timer0
Octal
Counter
10
Overflow
SIOIF
Clock
11
Serial communication
Interrupt
“11”
MUX
SCLK PIN
not “11”
SCK[1:0]
IOSW
SOUT
SOUT
PIN
IOSWIN
IOSWIN
1
0
Input shift register
SIN PIN
Shift
SIOR
Internal Bus
Figure 14-1 SPI Block Diagram
MAR. 2000 Ver 1.00
65
HYNIX [ HYNIX SEMICONDUCTOR ]
