sc16c2550b NXP Semiconductors, sc16c2550b Datasheet - Page 10

• Manufacturer Part Number: sc16c2550b
• Description: 5 V, 3.3 V And 2.5 V Dual Uart, 5 Mbit/s Max. , With 16-byte Fifos
• Manufacturer: NXP Semiconductors

NXP Semiconductors
SC16C2550B_4
Product data sheet
6.2 Internal registers
Table 4.
The SC16C2550B provides two sets of internal registers (A and B) consisting of
12 registers each for monitoring and controlling the functions of each channel of the
UART. These registers are shown in
registers (THR/RHR), interrupt 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).
Table 5.
[1]
[2]
Chip Select
CSA, CSB = 1
CSA = 0
CSB = 0
A2
General register set (THR/RHR, IER/ISR, MCR/MSR, FCR, LSR, SPR)
0
0
0
0
1
1
1
1
Baud rate register set (DLL/DLM)
0
0
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
Serial port selection
Internal registers decoding
A0
0
1
0
1
0
1
0
1
0
1
5 V, 3.3 V and 2.5 V dual UART, 5 Mbit/s (max.), with 16-byte FIFOs
Rev. 04 — 15 February 2007
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
Function
none
UART channel A
UART channel B
[2]
Table
5. The UART registers function as data holding
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
SC16C2550B
[1]
© NXP B.V. 2007. All rights reserved.
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