Table of Contents
Advertisement
(1) Serial I/O shift register 1 (SIO1)
This is an 8-bit register to carry out parallel/serial conversion and to carry out serial transmission/reception (shift
operation) in synchronization with the serial clock.
SIO1 is set with an 8-bit memory manipulation instruction.
When value in bit 7 (CSIE1) of serial operating mode register 1 (CSIM1) is 1, writing data to SIO1 starts serial
operation.
In transmission, data written to SIO1 is output to the serial output (SO1). In reception, data is read from the serial
input (SI1) to SIO1.
RESET input makes SIO1 undefined.
Caution Do not write data to SIO1 while the automatic transmit/receive function is activated.
(2) Automatic data transmit/receive address pointer (ADTP)
This register stores the value of (the number of transmit data bytes – 1) while the automatic transmit/receive
function is activated. It is decremented automatically with data transmission/reception.
ADTP is set with an 8-bit memory manipulation instruction. The high-order 3 bits must be set to 0.
RESET input sets ADTP to 00H.
Caution Do not write data to ADTP while the automatic transmit/receive function is activated.
(3) Serial clock counter
This counter counts the serial clocks to be output and input during transmission/reception and to check whether
8-bit data has been transmitted/received.
www.DataSheet4U.com
412
CHAPTER 17 SERIAL INTERFACE CHANNEL 1
Advertisement
Table of Contents
