SC16IS740IPW PHILIPS [NXP Semiconductors], SC16IS740IPW Datasheet - Page 16

• Manufacturer Part Number: SC16IS740IPW
• Description: Single UART with I2C-bus/SPI interface, 64 bytes of transmit and receive FIFOs, IrDA SIR built-in support
• Manufacturer: PHILIPS [NXP Semiconductors]

NXP Semiconductors
SC16IS740_750_760_5
Product data sheet
7.5.1 Interrupt mode operation
7.5.2 Polled mode operation
In Interrupt mode (if any bit of IER[3:0] is 1) the host is informed of the status of the
receiver and transmitter by an interrupt signal, IRQ. Therefore, it is not necessary to
continuously poll the Line Status Register (LSR) to see if any interrupt needs to be
serviced.
In Polled mode (IER[3:0] = 0000) the status of the receiver and transmitter can be
checked by polling the Line Status Register (LSR). This mode is an alternative to the FIFO
Interrupt mode of operation where the status of the receiver and transmitter is
automatically known by means of interrupts sent to the CPU.
Polled mode operation.
Fig 12. Interrupt mode operation
Fig 13. FIFO Polled mode operation
Figure 12
HOST
HOST
shows Interrupt mode operation.
Rev. 05 — 16 November 2006
Single UART with I
read LSR
read IIR
IRQ
2
C-bus/SPI interface, 64-byte FIFOs, IrDA SIR
SC16IS740/750/760
THR
THR
LSR
IER
IER
IIR
Figure 13
1
0
1
0
RHR
RHR
1
002aab042
0
002aab043
1
0
© NXP B.V. 2006. All rights reserved.
shows FIFO
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