Datasheet

© 2007 Microchip Technology Inc. Preliminary DS39631B-page 351
PIC18F2420/2520/4420/4520
FIGURE 26-14: EXAMPLE SPI SLAVE MODE TIMING (CKE = 0)
TABLE 26-16: EXAMPLE SPI MODE REQUIREMENTS (SLAVE MODE TIMING, CKE = 0)
Param
No.
Symbol Characteristic Min Max Units Conditions
70 TssL2scH,
Tss L2s cL
SS
to SCK or SCK Input TCY —ns
71 TscH SCK Input High Time
(Slave mode)
Continuous 1.25 T
CY + 30 ns
71A Single Byte 40 ns (Note 1)
72 TscL SCK Input Low Time
(Slave mode)
Continuous 1.25 TCY + 30 ns
72A Single Byte 40 ns (Note 1)
73 TdiV2scH,
TdiV2scL
Setup Time of SDI Data Input to SCK Edge 100 ns
73A Tb2b Last Clock Edge of Byte 1 to the First Clock Edge of Byte 2 1.5 T
CY + 40 ns (Note 2)
74 TscH2diL,
Tsc L2d iL
Hold Time of SDI Data Input to SCK Edge 100 ns
75 TdoR SDO Data Output Rise Time PIC18FXXXX 25 ns
PIC18LFXXXX 45 ns V
DD = 2.0V
76 TdoF SDO Data Output Fall Time 25 ns
77 TssH2doZ SS
to SDO Output High-Impedance 10 50 ns
78 TscR SCK Output Rise Time (Master mode) PIC18FXXXX 25 ns
PIC18LFXXXX 45 ns V
DD = 2.0V
79 TscF SCK Output Fall Time (Master mode) 25 ns
80 TscH2doV,
TscL2doV
SDO Data Output Valid after SCK Edge PIC18FXXXX 50 ns
PIC18LFXXXX 100 ns V
DD = 2.0V
83 TscH2ssH,
Tsc L2s sH
SS
after SCK edge 1.5 TCY + 40 ns
Note 1: Requires the use of Parameter #73A.
2: Only if Parameter #71A and #72A are used.
SS
SCK
(CKP = 0)
SCK
(CKP = 1)
SDO
SDI
70
71 72
73
74
75, 76
77
78
79
80
79
78
SDI
MSb LSb
bit 6 - - - - - -1
MSb In
bit 6 - - - -1 LSb In
83
Note: Refer to Figure 26-4 for load conditions.