Datasheet
V850ES/JG3-H, V850ES/JH3-H CHAPTER 17 ASYNCHRONOUS SERIAL INTERFACE C (UARTC)
R01UH0042EJ0500 Rev.5.00 Page 737 of 1513
Aug 12, 2011
(8) UARTCn transmit data register L (UCnTXL), UARTCn transmit data register (UCnTX)
The UCnTXL and UCnTX register is an 8-bit or 9-bit register used to set transmit data.
During LSB-first transmission when the data length has been specified as 7 bits, the transmit data is transferred to
bits 6 to 0 of the UCnRX register. During MSB-first transmission, the receive data is transferred to bits 7 to 1 of the
UCnRX register.
The access unit or reset value differs depending on the character length.
• Character length 7/8-bit (UCnOPT1.UCnEBE = 0)
This register can be read or written in 8-bit units.
Reset sets this register to FFH.
• Character length 9-bit (UCnOPT1.UCnEBE = 0)
This register can be read or written in 16-bit units.
Reset sets this register to 01FFH.
Cautions 1. In the transmission operation enable status (UCnPWR = 1 and UCnTXE = 1), Writing to the
UCnTXL, UCnTX register, as operate as trigger of transmission star, if writing the value of as
soon as before and save value, before the INTUCnT interrupt is occurred, the same data is
transferred at twice.
2. Data writing for consecutive transmission, after be generated the INTUCnT interrupt.
If writing the next data before the INTUCnT interrupt is occurred, transmission start
processing and source of conflict writing the UCnTXL, UCnTX register, unexpected
operations may occur.
3. If perform to write the UCnTXL, UCnTXLin the disable transmission operation register, can not
be used as transmission start trigger. Consequently, even if transmission enable status after
perform to write the UCnTXL, UCnTX register in the disable transmission operation
status, can not be started transmission.
(a) Character length 7/8-bit (UCnOPT1.UCnEBE = 0)
UCnTXL
(n = 0 to 4)
654321
After reset: FFH R/W Address: UC0TXL FFFFFA08H, UC1TXL FFFFFA18H,
UC2TXL FFFFFA28H, UC3TXL FFFFFA38H,
UC4TXL FFFFFA48H
7 0
(b) Character length 9-bit (UCnOPT1.UCnEBE = 1)
After reset: 01FFH R/W Address: UC0TX FFFFFA08H, UC1TX FFFFFA18H,
UC2TX FFFFFA28H, UC3TX FFFFFA38H,
UC4TX FFFFFA48H
UCnTX
(n = 0 to 4)
65432170
0000000
14 13 12 11 10 915 8