GMS81C2012 Datasheet, PDF (67/107 Pages) Hynix Semiconductor – HYUNDAI MICRO ELECTRONICS 8-BIT SINGLE-CHIP MICROCONTROLLERS

HYUNDAI MicroElectronics
GMS81C2012/GMS81C2020
14.1 Transmission/Receiving Timing
The serial transmission is started by setting SIOST(bit1 of
SIOM) to “1”. After one cycle of SCK, SIOST is cleared
automatically to “0”. The serial output data from 8-bit shift
register is output at falling edge of SCLK. And input data
is latched at rising edge of SCLK pin. When transmission
clock is counted 8 times, serial I/O counter is cleared as
‘0”. Transmission clock is halted in “H” state and serial I/
O interrupt(IFSIO) occurred.
SIOST
SCLK [R53]
(POL=0)
SOUT [R55]
SIN [R54]
(IOSW=0)
IOSWIN [R55]
(IOSW=1)
SIOSF
(SPI Status)
SPIIF
(SPI Int. Req)
D0
D1
D2
D3
D4 D5
D6
D7
D0
D1
D2
D3
D4
D5
D6
D7
D0
D1
D2
D3
D4
D5
D6
D7
Figure 14-3 SPI Timing Diagram at POL=0
SIOST
SCLK [R53]
(POL=1)
SOUT [R55]
SIN [R54]
(IOSW=0)
IOSWIN [R55]
(IOSW=1)
SIOSF
(SPI Status)
SPIIF
(SPI Int. Req)
D0
D1
D2
D3
D4 D5
D6
D7
D0
D1
D2
D3
D4
D5
D6
D7
D0
D1
D2
D3
D4
D5
D6
D7
Figure 14-4 SPI Timing Diagram at POL=1
MAR. 2000 Ver 1.00
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