
PIC18FXX39
DS30485A-page 132
Preliminary
2002 Microchip Technology Inc.
FIGURE 16-5:
SPI MODE WAVEFORM (SLAVE MODE WITH CKE = 0)
FIGURE 16-6:
SPI MODE WAVEFORM (SLAVE MODE WITH CKE = 1)
SCK
(CKP = 1
SCK
(CKP = 0
Input
Sample
SDI
bit7
bit0
SDO
bit7
bit6
bit5
bit4
bit3
bit2
bit1
bit0
SSPIF
Interrupt
(SMP = 0)
CKE = 0)
(SMP = 0)
Write to
SSPBUF
SSPSR to
SSPBUF
SS
Flag
Optional
Next Q4 cycle
after Q2
↓
SCK
(CKP = 1
SCK
(CKP = 0
Input
Sample
SDI
bit7
bit0
SDO
bit7
bit6
bit5
bit4
bit3
bit2
bit1
bit0
SSPIF
Interrupt
(SMP = 0)
CKE = 1)
(SMP = 0)
Write to
SSPBUF
SSPSR to
SSPBUF
SS
Flag
Not Optional
Next Q4 cycle
after Q2
↓