SC16C850L Datasheet, PDF (31/54 Pages) NXP Semiconductors – 1.8 V single UART, 5 Mbit/s (max.) with 128-byte FIFOs, infrared (IrDA) and 16 mode or 68 mode parallel bus interface

NXP Semiconductors
SC16C850L
1.8 V single UART with 128-byte FIFOs and IrDA encoder/decoder
7.9 Extra Feature Control Register (EFCR)
This is a write-only register, and it allows the software access to these registers: ‘first extra
feature register set’, ‘second extra feature register set’, Transmit FIFO Level Counter
(TXLVLCNT), and Receive FIFO Level Counter (RXLVLCNT).
Table 22. Extra Feature Control Register bits description
Bit
Symbol
Description
7:3
EFCR[7:3] reserved
2:1
EFCR[2:1] Enable Extra Feature Control bits
00 = General register set is accessible
01 = First extra feature register set is accessible
10 = Second extra feature register set is accessible
11 = reserved
0
EFCR[0]
Enable TXLVLCNT and RXLVLCNT access
0 = TXLVLCNT and RXLVLCNT are disabled
1 = TXLVLCNT and RXLVLCNT are enabled and can be read.
Remark: EFCR[2:1] has higher priority than EFCR[0]. TXLVLCNT and RXLVLCNT can
only be accessed if EFCR[2:1] are zeroes.
7.10 Scratchpad Register (SPR)
The SC16C850L provides a temporary data register to store 8 bits of user information.
7.11 Divisor Latch (DLL and DLM)
These are two 8-bit registers which store the 16-bit divisor for generation of the baud clock
in the baud rate generator. DLM, stores the most significant part of the divisor. DLL stores
the least significant part of the divisor.
7.12 Transmit FIFO Level Count (TXLVLCNT)
This register is a read-only register. It reports the number of spaces available in the
transmit FIFO.
7.13 Receive FIFO Level Count (RXLVLCNT)
This register is a read-only register. It reports the fill level of the receive FIFO (the number
of characters in the RX FIFO).
SC16C850L_4
Product data sheet
Rev. 04 — 13 December 2007
© NXP B.V. 2007. All rights reserved.
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