Datasheet

Electrical characteristics
i.MX 8QuadXPlus and 8DualXPlus Automotive and Infotainment Applications Processors, Rev. 0, 11/2018
PRELIMINARY NXP Semiconductors96
4.10.15.0.3 UART IrDA Mode Timing
The following subsections give the UART transmit and receive timings in IrDA mode.
UART IrDA Mode Transmitter
The following figure depicts the UART IrDA mode transmit timing, with 8 data bit/1 stop bit format.
Table 93 lists the transmit timing characteristics.
Figure 55. UART IrDA Mode Transmit Timing Diagram
UART IrDA Mode Receiver
The following figure depicts the UART IrDA mode receive timing, with 8 data bit/1 stop bit format.
Table 94 lists the receive timing characteristics.
Figure 56. UART IrDA Mode Receive Timing Diagram
Table 93. IrDA Mode Transmit Timing Parameters
ID Parameter Symbol Min Max Unit
UA3 Transmit Bit Time in IrDA mode t
TIRbit
1/F
baud_rate
1
– T
ref_clk
2
1
F
baud_rate
: Baud rate frequency. The maximum baud rate the UART can support is (LPUART_clk frequency)/(SBR[12:0] ×
(OSR+1)).
2
T
ref_clk
: The period of UART reference clock ref_clk (LPUART_clk after SBR divider).
1/F
baud_rate
+ T
ref_clk
—
UA4 Transmit IR Pulse Duration t
TIRpulse
(TNP+1)/(OSR+1) × (1/F
baud_rat
e
) – T
ref_clk
(TNP+1)/(OSR+1) × (1/F
baud_rat
e
) + T
ref_clk
—
Table 94. IrDA Mode Receive Timing Parameters
ID Parameter Symbol Min Max Unit
UA5 Receive Bit Time
1
in IrDA mode
1
The UART receiver can tolerate 1/((OSR+1) × Fbaud_rate) tolerance in each bit. But accumulation tolerance in one frame
must not exceed 3/((OSR+1) × Fbaud_rate).
t
RIRbit
1/F
baud_rate
2
–
1/(16 × F
baud_rate
)
1/F
baud_rate
+
1/(16 × F
baud_rate
)
—
UA6 Receive IR Pulse Duration t
RIRpulse
1.41 μs(5/16)× (1/F
baud_rate
)—
Bit 1
Bit 2
Bit 0
Bit 4 Bit 5 Bit 6 Bit 7
UARTx_TX_DATA
(output)
Bit 3
Start
Bit
STOP
BIT
POSSIBLE
PAR IT Y
BIT
UA3
UA3
UA3
UA3
UA4
Bit 1
Bit 2
Bit 0
Bit 4 Bit 5 Bit 6 Bit 7Bit 3
STOP
BIT
POSSIBLE
PAR ITY
BIT
UA5
UA5
UA5
UA5
UA6
Start
Bit
UARTx_RX_DATA
(input)