Datasheet

381
32133D–11/2011
UC3D
21.7.3.2 Master mode flow diagram
Figure 21-6. Master Mode Flow Diagram
SPI Enable
CSAAT ?
PS ?
1
0
0
1
1
NPCS = TDR(PCS) NPCS = MR(PCS)
Delay DLYBS
Serializer = TDR(TD)
TDRE = 1
Data Transfer
RDR(RD) = Serializer
RDRF = 1
TDRE ?
NPCS = 0xF
Delay DLYBCS
Fixed
peripheral
Variable
peripheral
Delay DLYBCT
0
1
CSAAT ?
0
TDRE ?
1
0
PS ?
0
1
TDR(PCS)
= NPCS ?
no
yes
MR(PCS)
= NPCS ?
no
NPCS = 0xF
Delay DLYBCS
NPCS = TDR(PCS)
NPCS = 0xF
Delay DLYBCS
NPCS = MR(PCS),
TDR(PCS)
Fixed
peripheral
Variable
peripheral
- NPCS defines the current Chip Select
- CSAAT, DLYBS, DLYBCT refer to the fields of the
Chip Select Register corresponding to the Current Chip Select
- When NPCS is 0xF, CSAAT is 0.