sc16c751b NXP Semiconductors, sc16c751b Datasheet - Page 6

• Manufacturer Part Number: sc16c751b
• Description: 5 V, 3.3 V And 2.5 V Uart With 64-byte Fifos
• Manufacturer: NXP Semiconductors

NXP Semiconductors
SC16C751B_2
Product data sheet
6.2 FIFO operation
status and control registers (IER/ISR), a FIFO Control Register (FCR), line status and
control registers (LCR/LSR), modem status and control registers (MCR/MSR),
programmable data rate (clock) control registers (DLL/DLM), and a user accessible
Scratchpad Register (SPR). Register functions are more fully described in the following
paragraphs.
Table 3.
[1]
[2]
The 64-byte transmit and receive data FIFOs are enabled by the FIFO Control Register
bit 0 (FCR[0]). The receiver FIFO section includes a time-out function to ensure data is
delivered to the external CPU. An interrupt is generated whenever the Receive Holding
Register (RHR) has not been read following the loading of a character or the receive
trigger level has not been reached.
Table 4.
A2
General register set (THR/RHR, IER/ISR, MCR/MSR, FCR, LCR/LSR, SPR)
0
0
0
0
1
1
1
1
Baud rate register set (DLL/DLM)
0
0
Selected trigger level
(characters)
16-byte FIFO
1
4
8
14
64-byte FIFO
1
16
32
56
These registers are accessible only when LCR[7] is a logic 0.
These registers are accessible only when LCR[7] is a logic 1.
A1
0
0
1
1
0
0
1
1
0
0
Internal registers decoding
Flow control mechanism
A0
0
1
0
1
0
1
0
1
0
1
Rev. 02 — 10 October 2008
READ mode
Receive Holding Register
Interrupt Enable Register
Interrupt Status Register
Line Control Register
Modem Control Register
Line Status Register
Modem Status Register
Scratchpad Register
LSB of Divisor Latch
MSB of Divisor Latch
INT pin activation
1
4
8
14
1
16
32
56
[2]
5 V, 3.3 V and 2.5 V UART with 64-byte FIFOs
Negate RTS
1
4
8
14
1
16
32
56
WRITE mode
Transmit Holding Register
Interrupt Enable Register
FIFO Control Register
Line Control Register
Modem Control Register
n/a
n/a
Scratchpad Register
LSB of Divisor Latch
MSB of Divisor Latch
SC16C751B
[1]
© NXP B.V. 2008. All rights reserved.
Assert RTS
0
0
0
0
0
0
0
0
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