W742C813 Datasheet, PDF (34/56 Pages) Winbond – 4 BIT MICROCONTROLLER

W742E/C813
T1
T2
T3
T4
Ins.
P0.0
data changed at falling edge
SOP R
1234 56 78
P0.0
data changed at rising edge
1234 56 78
Data latch
BUSYO
(PSR2.3)
EVF5
P0.1
NOTE: The serial clock frequency is fosc/2
Figure 5-13 Timing of the Serial Output Function (SOP R)
Port Status Register 2 (PSR2)
Port status register 2 is organized as 4-bit binary register (PSR2.0 to PSR2.3). PSR2 is controlled
by the MOVA R, PSR2, and CLR PSR2 instructions. The bit descriptions are as follows:
3
2
PSR2 R
1
0
R
Note: R means read only.
Bit 0 is reserved.
Bit 1 (BUSYI): Serial port input busy flag.
Bit 2 is reserved.
Bit 3 (BUSYO): Serial port output busy flag.
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