Figure 28 an – Rainbow Electronics AT75C220 User Manual

Page 123

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AT75C220

123

Figure 28. Functional Flow Diagram in Master Mode

SPI Enable

TDRE

PS

1

0

0

1

1

1

0

Same peripheral

New peripheral

NPCS = SP_TDR(PCS)

NPCS = SP_MR(PCS)

Delay DLYBS

Serializer = SP_TDR(TD)

TDRE = 1

Data Transfer

SP_RDR(RD) = Serializer

RDRF = 1

TDRE

PS

NPCS = 0xF

Delay DLYBCS

SP_TDR(PCS)

NPCS = 0xF

Delay DLYBCS

NPCS = SP_TDR(PCS)

Fixed peripheral

Variable peripheral

Fixed peripheral

Variable peripheral

Delay DLYBCT

0