Intel E3815 FH8065301567411 Data Sheet

Product codes
FH8065301567411
Page of 5308
 
PCU – Universal Asynchronous Receiver/Transmitter (UART)
Intel
®
 Atom™ Processor E3800 Product Family
Datasheet
4419
32.5
IO Mapped Registers
There are 12 registers associated with the UART. These registers share eight address 
locations in the IO address space. 
 shows the registers and their addresses as 
offsets of a base address. Note that the state of the COM1_LCR.DLAB register bit, 
which is the most significant bit (MSB) of the Serial Line Control register, affects the 
selection of certain of the UART registers. The COM1_LCR.DLAB register bit must be set 
high by the system software to access the Baud Rate Generator Divisor Latches.
Notes:
1.
These registers are consolidated in the Receiver Buffer / Transmitter Holding Register 
(COM1_RX_TX_BUFFER)
2.
These registers are consolidated in the Interrupt Enable Register (COM1_IER)
3.
These registers are consolidated in the Interrupt Identification / FIFO Control Register (COM1_IIR)
4.
These registers are implemented but unused since the UART signals related to modem interaction are 
not implemented.
§ 
Table 306.
Register Access List  
Register Address
(Offset to Base 
IO Address)
COM1_LCR.DLA
B Value
Register 
Access 
Type
Register Accessed
0h
0b
RO
Receiver Buffer
1
0h
0b
WO
Transmitter Holding
1
0h
1b
RW
Divisor Latch LSB (Lowest Significant Bit)
1
1h
0b
RW
Interrupt Enable
2
1h
1b
RW
Divisor Latch MSB (Most Significant Bit)
2
2h
xb
RO
Interrupt Identification
3
2h
xb
WO
FIFO Control
3
3h
xb
RW
Line Control
4h
xb
RW
Modem Control
4
5h
xb
RO
Line Status
6h
xb
RO
Modem Status
4
7h
xb
RW
Scratchpad