CHAPTER 19 SERIAL INTERFACE UNIT 1 (SIU1)
User’s Manual U14272EJ3V0UM
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19.3.4 SIUIE_1 (0x0C00 0011: LCR7 = 0)
Bit
7
6
5
4
3
2
1
0
Name
Reserved
Reserved
Reserved
Reserved
IE3
IE2
IE1
IE0
R/W
R
R
R
R
R/W
R/W
R/W
R/W
RTCRST
0
0
0
0
0
0
0
0
Other resets
0
0
0
0
0
0
0
0
Bit
Name
Function
7 to 4
Reserved
0 is returned when read
3
IE3
Modem status interrupt
1 : Enable
0 : Prohibit
2
IE2
Receive status interrupt
1 : Enable
0 : Prohibit
1
IE1
Transmit holding register empty interrupt
1 : Enable
0 : Prohibit
0
IE0
Receive data ready interrupt or character timeout interrupt in FIFO mode
1 : Enable
0 : Prohibit
This register is used to specify interrupt enable/prohibit settings for the five types of interrupt requests used in the
SIU1.
An interrupt is enabled by setting the corresponding bit to 1.
Overall use of interrupt functions can be halted by setting bits 0 to 3 of this register to 0.
When interrupts are prohibited, “pending” is not displayed in the IIR0 bit in the SIUIID_1 register even when
interrupt conditions have been met.
Other functions in the SIU1 are not affected even though interrupts are prohibited and the settings in the SIULS_1
register and SIUMS_1 register are valid.
To access this register, set the LCR7 bit (bit 7 of the SIULC_1 register) to 0.