80C251SB16 Datasheet, PDF (31/36 Pages) Intel Corporation – HIGH-PERFORMANCE CHMOS MICROCONTROLLER

8XC251SA/SB/SP/SQ HIGH-PERFORMANCE CHMOS MICROCONTROLLER
5.4 AC Characteristics — Serial Port, Shift Register Mode
Symbol
Table 14. Serial Port Timing — Shift Register Mode
Parameter
Min
Max
T_XLXL
T_QVSH
T_XHQX
T_XHDX
T_XHDV
Serial Port Clock Cycle Time
Output Data Setup to Clock Rising Edge
Output Data hold after Clock Rising Edge
Input Data Hold after Clock Rising Edge
Clock Rising Edge to Input Data Valid
12T_OSC
10T_OSC – 133
2T_OSC – 117
0
10T_OSC – 133
Units
ns
ns
ns
ns
ns
TXLXL
TXD
RXD
(Out)
RXD
(In)
TXHQX
TQVXH
0
1
2
TXHDV
Valid
Valid
TXHDX
Valid
3
TAV^†
Valid
4
Valid
5
Valid
6
Valid
†_{TI and RI are set during S1P1 of the peripheral cycle following the shift of the eighth bit.}
Figure 17. Serial Port Waveform — Shift Register Mode
Set TI^†
7
Set RI^†
Valid
A2592-02
5.5 External Clock Drive
Symbol
Table 15. External Clock Drive
Parameter
Min
1/T_CLCL
Oscillator Frequency (F_OSC)
T_CHCX
High Time
20
T_CLCX
Low Time
20
T_CLCH
Rise Time
T_CHCL
Fall Time
Max
16
10
10
Units
MHz
ns
ns
ns
ns
PRELIMINARY
31