SC68C752BIBS NXP Semiconductors, SC68C752BIBS Datasheet - Page 16

• Manufacturer Part Number: SC68C752BIBS
• Manufacturer: NXP Semiconductors

Specifications of SC68C752BIBS

• Number Of Channels: 2
• Transmit Fifo: 64Byte
• Receive Fifo: 64Byte
• Transmitter And Receiver Fifo Counter: Yes
• Data Rate: 5Mbps
• Operating Supply Voltage (max): 5.5V
• Mounting: Surface Mount
• Pin Count: 32
• Operating Temperature (min): -40C
• Operating Temperature (max): 85C
• Operating Temperature Classification: Industrial
• Lead Free Status / Rohs Status: Compliant

NXP Semiconductors
SC68C752B_4
Product data sheet
6.6.2.1 Transmitter
6.6.2.2 Receiver
6.6.2 Block DMA transfers (DMA mode 1)
6.7 Sleep mode
Figure 11
TXRDYn is active when there is a trigger level number of spaces available. It becomes
inactive when the FIFO is full.
RXRDYn becomes active when the trigger level has been reached, or when a time-out
interrupt occurs. It will go inactive when the FIFO is empty or an error in the receive FIFO
is flagged by LSR[7].
Sleep mode is an enhanced feature of the SC68C752B UART. It is enabled when EFR[4],
the enhanced functions bit, is set and when IER[4] is set. Sleep mode is entered when:
Remark: Sleep mode will not be entered if there is data in the receive FIFO.
In Sleep mode, the UART clock and baud rate clock are stopped. Since most registers are
clocked using these clocks, the power consumption is greatly reduced. The UART will
wake up when any change is detected on the RXn line, when there is any change in the
state of the modem input pins, or if data is written to the transmit FIFO.
Remark: Writing to the divisor latches, DLL and DLM, to set the baud clock, must not be
done during Sleep mode. Therefore, it is advisable to disable Sleep mode using IER[4]
before writing to DLL or DLM.
Fig 11. TXRDYn and RXRDYn in DMA mode 1
•
•
•
The serial data input line, RXn, is idle (see
conditions”).
The transmit FIFO and transmit shift register are empty.
There are no interrupts pending except THR and time-out interrupts.
trigger
wrptr
wrptr
level
shows TXRDYn and RXRDYn in DMA mode 1.
transmit
5 V, 3.3 V and 2.5 V dual UART, 5 Mbit/s (max.), with 64-byte FIFOs
Rev. 04 — 20 January 2010
FIFO full
TXRDYn
TXRDYn
Section 6.8 “Break and time-out
trigger
rdptr
rdptr
level
FIFO EMPTY
receive
SC68C752B
at least one
location filled
© NXP B.V. 2010. All rights reserved.
RXRDYn
RXRDYn
002aaa234
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