Fujitsu FR81S User Manual
CHAPTER 40: MULTI-FUNCTION SERIAL INTERFACE
6. Operation of CSIO
FUJITSU SEMICONDUCTOR LIMITED
CHAPTER : MULTI-FUNCTION SERIAL INTERFACE
FUJITSU SEMICONDUCTOR CONFIDENTIAL
234
Figure 6-29 Round Operation of Chip Select (SST1 and SST0=0, SED1 and SED0=3,
CSEN3=1, CSEN2=0, CSEN1=0, CSEN0=1, SCAM=0)
SCK
・・・
・・・
・・・
・・・
・・・
・・・
SCS0
SCS3
・・・
・・・
・・・
・・・
SCS0
SCD
SCS3
・・・
SCS0
・・・
SCS3
TBYTE0
TBYTE3
*1:Internal counter to be count transmission bytes
N
N-1
0
I
I -1
・・・
・・・
0
N
N -1
・・・
0
Transmissions
counter*1
counter*1
N
I
Load
Load
Notes:
⋅
When transmission operation disabled (SCR:TXE=0) is changed to enabled (SCR:TXE=1), the serial
chip select pin specified by the serial chip select start bit (SCSCR:SST1 and SST0) becomes active first.
⋅
When the serial chip select maintains its active level (SCSCR:SCAM=1), it does not transit to the next
serial chip pin even if transmission data is written to the transmission bus idle (SCR:TBI=1).
⋅
At the round operation, timing adjustment of the serial chip select pin (setup time, hold time, deselection
time) is valid.
⋅
After a software reset (SCR:UPCL=1), the serial chip select pin specified by the serial chip select start
bit (SCSCR:SST1 and SST0) becomes active first.
MB91520 Series
MN705-00010-1v0-E
1547