UPD784026 Renesas Electronics Corporation., UPD784026 Datasheet - Page 457

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

(1) Shift register (SIO1/SIO2)
(2) SO latch
(3) Serial clock selector
(4) Serial clock counter
(5) Interrupt signal generator
(6) Serial clock control circuit
(7) Direction control circuit
The SIO1 and SIO2 converts 8-bit serial data to 8-bit parallel data, and vice versa. SIO1/SIO2 is used for both
transmission and reception.
Actual transmit/receive operations are controlled by writing to/reading from SIO1/SIO2.
Reading/writing can be performed by 8-bit manipulation instruction.
The contents of SIO1/SIO2 are undefined after RESET input.
The SO latch holds the SO1/SO2 pin output level.
Selects the serial clock to be used.
Counts the serial clocks output or input in a transmit/receive operation, and checks that 8-bit data transmission/reception
has been performed.
Generates an interrupt request when 8 serial clocks have been counted by the serial clock counter.
Controls the supply of the serial clock to the shift register, and also controls the clock output to the SCK1/SCK2 pins
when the internal clock is used.
Switches between MSB-first and LSB-first modes.
CHAPTER 16 ASYNCHRONOUS SERIAL INTERFACE/3-WIRE SERIAL I/O
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