XR21B1421 Datasheet, PDF (36/50 Pages) Exar Corporation – Enhanced 1-Ch Full-Speed

XR21B1421
Table 16: IR Mode Bit Positions
Bit
Description
7:3 Reserved
2 TX_PULSE
0: Transmit pulses are 3/16th of and centered in the bit period
1: Transmit pulses are 4/16th of and centered in the bit period
1 RX_INVERT
0: Standard IrDA receive data
1: Non-standard inverted receive data
0 EN
0: Disable IR mode
1: Enable IR mode
GET / SET_XCVR_EN_DELAY
Transfer Type: Control In / Out
Transfer Size: 2 bytes
The GET / SET_XCVR_EN_DELAY report gets or sets the delay in deasserting the or auto RS-485 half-duplex enable.
Field
Report ID
Delay
Offset
0
1
Size
1
1
Value
0x57
See Table 17
Description
Get / Set auto RS-485 half-duplex enable delay
Values from 0 - 15 baud times
Table 17: Delay Bit Positions
Bit
7:4 Reserved
3:0 Delay
Description
GET / SET_FLOW_CTRL_THRESHOLD
Transfer Type: Control In / Out
Transfer Size: 3 bytes
The GET / SET_FLOW_CTRL_THRESHOLD report gets or sets flow control threshold used in hardware and software flow
control. The default flow control threshold is 0x1C2 or 450 decimal. For hardware flow control RTS or DTR will be deas-
serted (high) when the receive FIFO exceeds the flow control threshold and asserted low at or below the threshold. For soft-
ware flow control the XOFF character is pushed into the transmit FIFO and transmitted to the remote UART above the
threshold and the XON character is transmitted at the threshold setting.
Field
Report ID
Offset
0
Size
1
Value
0x58
Description
Get / Set auto RS-485 half-duplex enable delay
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