CHAPTER 10 SERIAL INTERFACE FUNCTION
User’s Manual U12688EJ4V0UM00
304
10.3.4 Basic operation
(1) Transfer format
CSIn transmits/receives data with three lines: one clock line and two data lines (n = 0 to 3).
A serial transfer starts when an instruction that writes transfer data to the SIOn register is executed.
In the case of transmission, data is output from the SOn pin at each falling edge of SCKn.
In the case of reception, data is latched through the SIn pin at each rising edge of SCKn.
SCKn stops when the serial clock counter overflows (at the rising edge of the 8th count), and SCKn remains
high until the next data transmission or reception is started. At the same time, a transmission/reception
complete interrupt (INTCSIn) is generated.
Caution Even if CTXEn bit is changed from 0 to 1 after the transmit data is written to the SIOnL
registers, serial transfer will not begin.
1
2
3
4
5
6
7
8
DI7 DI6 DI5 DI4 DI3 DI2 DI1 DI0
SCKn
SIn
SOn
Serial transmission/reception completed
Interrupt generation
Transfer start in synchronization with falling of SCKn
Execution of write instruction to SIOn register
INTCSIn interrupt
Remark
n = 0 to 3
Summary of Contents for V850E/MS1 UPD703100
Page 2: ...User s Manual U12688EJ4V0UM00 2 MEMO ...
Page 6: ...User s Manual U12688EJ4V0UM00 6 MEMO ...
Page 8: ...User s Manual U12688EJ4V0UM00 8 MEMO ...
Page 12: ...User s Manual U12688EJ4V0UM00 12 MEMO ...
Page 26: ...User s Manual U12688EJ4V0UM00 26 MEMO ...
Page 68: ...User s Manual U12688EJ4V0UM00 68 MEMO ...
Page 124: ...User s Manual U12688EJ4V0UM00 124 MEMO ...
Page 198: ...User s Manual U12688EJ4V0UM00 198 MEMO ...
Page 230: ...User s Manual U12688EJ4V0UM00 230 MEMO ...