SC68C752BIBS,157 NXP Semiconductors, SC68C752BIBS,157 Datasheet - Page 29

• Manufacturer Part Number: SC68C752BIBS,157
• Description: IC UART DUAL 32HVQFN
• Manufacturer: NXP Semiconductors

Specifications of SC68C752BIBS,157

• Number Of Channels: 2, DUART
• Fifo's: 64 Byte
• Voltage - Supply: 2.5V, 3.3V, 5V
• With Auto Flow Control: Yes
• With False Start Bit Detection: Yes
• With Modem Control: Yes
• Mounting Type: Surface Mount
• Package / Case: 32-VFQFN Exposed Pad
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: 935280969157; SC68C752BIBS; SC68C752BIBS

NXP Semiconductors
SC68C752B_4
Product data sheet
7.10 Enhanced Feature Register (EFR)
7.12 Transmission Control Register (TCR)
7.11 Divisor latches (DLL, DLM)
This 8-bit register enables or disables the enhanced features of the UART.
shows the Enhanced Feature Register bit settings.
Table 20.
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.
Note that DLL and DLM can only be written to before Sleep mode is enabled, that is,
before IER[4] is set.
This 8-bit register is used to store the receive FIFO threshold levels to stop/start
transmission during hardware/software flow control.
register bit settings.
Table 21.
TCR trigger levels are available from 0 bytes to 60 bytes with a granularity of four.
Bit
7
6
5
4
3:0
Bit
7:4
3:0
Symbol
TCR[7:4]
TCR[3:0]
Symbol
EFR[7]
EFR[6]
EFR[5]
EFR[4]
EFR[3:0] Combinations of software flow control can be selected by programming these
Enhanced Feature Register bits description
Transmission Control Register bits description
Description
CTS flow control enable.
RTS flow control enable.
Special character detect.
Enhanced functions enable bit.
bits. See
Description
receive FIFO trigger level to resume transmission (0 bytes to 60 bytes).
receive FIFO trigger level to halt transmission (0 bytes to 60 bytes).
5 V, 3.3 V and 2.5 V dual UART, 5 Mbit/s (max.), with 64-byte FIFOs
logic 0 = CTS flow control is disabled (normal default condition)
logic 1 = CTS flow control is enabled. Transmission will stop when a HIGH
signal is detected on the CTSn pin.
logic 0 = RTS flow control is disabled (normal default condition)
logic 1 = RTS flow control is enabled. The RTSn pin goes HIGH when the
receiver FIFO halt trigger level TCR[3:0] is reached, and goes LOW when the
receiver FIFO resume transmission trigger level TCR[7:4] is reached.
logic 0 = special character detect disabled (normal default condition)
logic 1 = special character detect enabled. Received data is compared with
Xoff2 data. If a match occurs, the received data is transferred to FIFO and
IIR[4] is set to a logic 1 to indicate a special character has been detected.
logic 0 = disables enhanced functions and writing to IER[7:4], FCR[5:4],
MCR[7:5]
logic 1 = enables the enhanced function IER[7:4], FCR[5:4], and MCR[7:5]
can be modified, that is, this bit is therefore a write enable
Rev. 04 — 20 January 2010
Table 4 “Software flow control options (EFR[3:0])” on page
Table 21
shows transmission control
SC68C752B
© NXP B.V. 2010. All rights reserved.
Table 20
9.
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