NEC PD78214 - Manual (Page 318)

289
Chapter 10 Clock Synchronous Serial Interface
10
Fig. 10-28 Sending a Command from Master Device to Slave Device
Program processing Hardware operation Program processing
SCK pin
12
345
6
78
SB0 pin
C7
Hardware operation
C6
C5
C4
C3
C2
C1
C0
ACK
READY
Command
Master device processing (transmitter) Transfer line Slave device processing (receiver)
Interrupt handling (preparation for next serial transfer)
Serial transmission
Generate
INTCSI
Serial reception
Generate
INTCSI
Output BUSY
Clear BUSY
BUSY
Set CMDT
Write to SIO
Set ACKD
Stop SCK
Read
SIO
Analyze command
Set ACKT
Clear BUSY
Set CMDD
Output ACK
Remark
This timing is valid only under the following conditions:
•
The master is only allowed to transmit a command.
•
The slave is only allowed to receive a command.
ACKE is set to 0 and BSYE is set to 1.