Ameba-D User Manual
User Manual All information provided in this document is subject to legal disclaimers. © REALTEK 2019. All rights reserved.
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Fig 14-5 Relationship between IrDA signal and UART signal
txd/rxd of sir encoder/decoder is then connected with optical transceiver.
14.3.4
Auto-flow Control
It is possible to control the serial UART data flow between 2 devices by using the nCTS (UCTS_) input and the nRTS (URTS_) output. Fig 14-6
shows how to connect 2 devices in auto-flow control mode.
Fig 14-6 Signal connection in auto-flow control mode
When auto-flow control mode is enabled, if input nCTS is deasserted in Tx idle state, the transmission doesn’t occur; if input nCTS is deasserted
during transmission, the current transmission is completed before the transmitter stops. When Rx FIFO is almost full, nRTS is deasserted to
inform peer device to stop transmission at the end of current transmission.
14.3.5
Interrupt Control
Table 14-5 gives the description of different interrupt.
Table 14-5 Description of different interrupt
ID
Priority Type
Source
Reset Control
3’b011 1st
Receiver Line Status
Parity, overrun or Framing errors or break interrupt
Read the LSR
3’b010 2nd
Receiver Data Available
Rx FIFO Trigger level reached or Rx FIFO full
FIFO drops below trigger level
3’b110 2nd
Timeout Indication
At least one character in the FIFO but no character
has been input to the FIFO or read from it for the last
4 characters times
Read the RBR or Clear Rx FIFO
3’b001 3rd
Tx FIFO empty
Tx FIFO empty
Write to the Tx FIFO or read the IIR
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2019-05-15 10:08:03