sc16c754bibm NXP Semiconductors, sc16c754bibm Datasheet - Page 27

• Manufacturer Part Number: sc16c754bibm
• Description: 5 V, 3.3 V And 2.5 V Quad Uart, 5 Mbit/s Max. With 64-byte Fifos
• Manufacturer: NXP Semiconductors

Philips Semiconductors
9397 750 14668
Product data sheet
7.6 Modem Control Register (MCR)
The MCR controls the interface with the modem, data set, or peripheral device that is
emulating the modem.
Table 14:
[1]
Bit
7
6
5
4
3
2
1
0
MCR[7:5] can only be modified when EFR[4] is set, that is, EFR[4] is a write enable.
Symbol
MCR[7]
MCR[6]
MCR[5]
MCR[4]
MCR[3]
MCR[2]
MCR[1]
MCR[0]
Modem Control Register bits description
[1]
[1]
[1]
5 V, 3.3 V and 2.5 V quad UART, 5 Mbit/s (max.) with 64-byte FIFOs
Description
Clock select.
TCR and TLR enable.
Xon Any.
Enable loop-back.
IRQ enable OP.
FIFO Ready enable.
RTS
DTR
Table 14
Rev. 02 — 13 June 2005
logic 0 = divide-by-1 clock input
logic 1 = divide-by-4 clock input
logic 0 = no action
logic 1 = enable access to the TCR and TLR registers
logic 0 = disable Xon Any function
logic 1 = enable Xon Any function
logic 0 = normal operating mode
Logic 1 = enable local loop-back mode (internal). In this mode the
MCR[3:0] signals are looped back into MSR[7:4] and the TX output is
looped back to the RX input internally.
logic 0 = forces INTA-INTB outputs to the 3-state mode and OP output
to HIGH state
logic 1 = forces the INTA-INTB outputs to the active state and OP
output to LOW state. In loop-back mode, controls MSR[7].
logic 0 = disable the FIFO Rdy register
logic 1 = enable the FIFO Rdy register. In loop-back mode, controls
MSR[6].
logic 0 = force RTS output to inactive (HIGH)
logic 1 = force RTS output to active (LOW).
In loop-back mode, controls MSR[4]. If Auto-RTS is enabled, the RTS
output is controlled by hardware flow control.
logic 0 = force DTR output to inactive (HIGH)
logic 1 = force DTR output to active (LOW).
In loop-back mode, controls MSR[5].
shows Modem Control Register bit settings.
© Koninklijke Philips Electronics N.V. 2005. All rights reserved.
SC16C754B
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