UPD784026 Renesas Electronics Corporation., UPD784026 Datasheet - Page 517

• Manufacturer Part Number: UPD784026
• Description: 16/8-bit Single-chip Microcontrollers
• Manufacturer: Renesas Electronics Corporation.

17.7 CAUTIONS
(1) When changing from “CTXE = 0, CRXE = 1” to “CTXE = 1, CRXE = 0”, and when changing from “CTXE = 1,
(2) When master/slave exchange processing is performed, since serial clock line (SCK) input/output switching is performed
(3) ACKT must not be set before the end of a transfer.
CRXE = 0” to “CTXE = 0, CRXE = 1”, ensure that this is not done with a single instruction, as this will result in misoperation
of the serial clock counter, and the first communication after the change will finish in fewer than 8 bits. Instead, two
instructions should be used as shown below.
Example To change “CTXE = 1, CRXE = 0” to “CTXE = 0, CRXE = 1”
asynchronously between master and slave, a pull-up resistor is also required for the serial clock line (SCK).
CLR1 CTXE
SET1 CRXE
CHAPTER 17 CLOCKED SERIAL INTERFACE
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