MAX14830 Datasheet, PDF (45/68 Pages) Maxim Integrated Products – Quad Serial UART with 128-Word FIFOs

MAX14830
Quad Serial UART with 128-Word FIFOs
TxFIFOLvl—Transmit FIFO Level Register
ADDRESS:
0x11
MODE:
R
BIT
7
6
5
4
NAME
TxFL7
TxFL6
TxFL5
TxFL4
RESET
0
0
0
0
3
TxFL3
0
2
TxFL2
0
1
TxFL1
0
0
TxFL0
0
Bits 7–0: TxFL[n]
The TxFIFOLvl register represents the current number of words in the Transmit FIFO.
RxFIFOLvl—Receive FIFO Level Register
ADDRESS:
MODE:
BIT
NAME
RESET
7
RxFL7
0
0x12
R
6
RxFL6
0
5
RxFL5
0
4
RxFL4
0
3
RxFL3
0
2
RxFL2
0
1
RxFL1
0
0
RxFL0
0
Bits 7–0: RxFL[n]
The RxFIFOLvl Level register represents the current number of words in the Receive FIFO.
FlowCtrl—Flow Control Register
ADDRESS:
MODE:
BIT
7
NAME SwFlow3
RESET
0
0x13
R/W
6
SwFlow2
0
5
SwFlow1
0
4
SwFlow0
0
3
SwFlowEn
0
2
GPIAddr
0
1
AutoCTS
0
0
AutoRTS
0
Bits 7–4: SwFlow[n]
The SwFlow[n] bits configure auto software flow control and/or special character detection in combination with the
characters defined in the XON1, XON2, XOFF1, and/or XOFF2 registers. See Table 4.
FlowCtrl[n] select which of the XON1, XON2, XOFF1, or/and XOFF2 characters are used for special character detec-
tion and/or auto flow control. If auto receiver flow control is enabled through SwFlowEn and FlowCtrl[n], the XON and
XOFF characters that the MAX14830 receives are filtered out and are not put into the RxFIFO. Set the SwFlowEn bit to
0 and set MODE2[4] to 1 to enable special character detection. Under these conditions, auto flow transmit flow control
is not used.
If both special character detection (MODE2[4]) and automatic software flow control (FlowCtrl[3]) are to be enabled,
XON1 and XOFF1 define the auto flow control characters while XON2 and XOFF2 define the special character detec-
tion characters.
Bit 3: SwFlowEn
The SwFlowEn bit enables automatic software flow control. The characters used for automatic software flow control are
selected in FlowCtrl[n]. If special character detection (MODE2[4] = 1) is used in addition to automatic software flow
control, XON1 and XOFF1 are used for flow control, while XON2 and XOFF2 define the special characters.
Maxim Integrated
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