SC16C2552 Philips Semiconductors, SC16C2552 Datasheet - Page 7

• Manufacturer Part Number: SC16C2552
• Description: Dual UART with 16-byte transmit and receive FIFOs
• Manufacturer: Philips Semiconductors

Philips Semiconductors
9397 750 11636
Product data
6.2 Internal registers
The SC16C2552 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
holding 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), a user accessible scratchpad register (SPR), and an Alternate Function
Register (AFR).
Table 4:
[1]
[2]
A2
General register set (THR/RHR, IER/ISR, MCR/MSR, FCR, LSR, SPR)
0
0
0
0
1
1
1
1
Register set 2 (DLL/DLM/AFR)
0
0
0
The General Register sets are accessible only when CS is a logic 0 and LCR[7] is a logic 0.
The Baud Rate register and AFR register sets are accessible only when CS is a logic 0 and LCR[7] is
a logic 1 for the register set (A/B) being accessed.
A1
0
0
1
1
0
0
1
1
0
0
1
Internal registers decoding
A0
0
1
0
1
0
1
0
1
0
1
0
Rev. 03 — 20 June 2003
READ mode
Receive Holding Register
Interrupt Status Register
Line Status Register
Modem Status Register
Scratchpad Register
LSB of Divisor Latch
MSB of Divisor Latch
Alternate Function Register
[2]
Dual UART with 16-byte transmit and receive FIFOs
Table
4. The UART registers function as data
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
Alternate Function Register
© Koninklijke Philips Electronics N.V. 2003. All rights reserved.
SC16C2552
[1]
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