402
CHAPTER 18 SERIAL INTERFACE CHANNEL 1
Start bit switching is realized by switching the bit order write to SIO1. The SIO1 shift order remains unchanged.
Thus, switching between MSB-first and LSB-first must be performed before writing data to SIO1.
(4) Transfer start
Serial transfer is started by setting transfer data to the serial I/O shift register 1 (SIO1) when the following two
conditions are satisfied.
•
Serial interface channel 1 operation control bit (CSIE1) = 1
•
Internal serial clock is stopped or SCK1 is a high level after 8-bit serial transfer.
Caution
If CSIE1 is set to "1" after data write to SIO1, transfer does not start.
Upon termination of 8-bit transfer, serial transfer automatically stops and the interrupt request flag (CSIIF1)
is set.
Figure 18-7. Circuit of Switching in Transfer Bit Order
7
6
Internal Bus
1
0
LSB-first
MSB-first
Read/Write Gate
SI1
Serial I/O Shift Register 1 (SIO1)
Read/Write Gate
SO1
SCK1
D
Q
SO1 Latch
Summary of Contents for PD78056F
Page 2: ...2 MEMO ...
Page 14: ...14 MEMO ...
Page 34: ...34 MEMO ...
Page 154: ...154 MEMO ...
Page 170: ...170 MEMO ...
Page 238: ...238 MEMO ...
Page 278: ...278 MEMO ...
Page 432: ...432 MEMO ...
Page 476: ...476 MEMO ...
Page 548: ...548 MEMO ...
Page 564: ...564 MEMO ...
Page 580: ...580 MEMO ...
Page 584: ...584 MEMO ...
Page 592: ...592 MEMO ...