NS16C2552TVA NSC [National Semiconductor], NS16C2552TVA Datasheet - Page 26

• Manufacturer Part Number: NS16C2552TVA
• Description: Dual UART with 16-byte/64-byte FIFOs and up to 5 Mbit/s Data Rate
• Manufacturer: NSC [National Semiconductor]

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6.0 Register Set
6.15 SOFTWARE FLOW CONTROL REGISTERS (SFR)
The following four registers are used as programmable soft-
ware flow control characters.
Bit
3:0
Bit
7:0
Bit
7:0
7:0
Bit
Bit
7:0
Bit Name
Software
Default
Control
Flow
Sel
Xoff2 Data
Bit Name
Xoff1 Data
Xon2 Data
Bit Name
Xon1 Data
Bit Name
Bit Name
R/W
R/W
Def
0
(Continued)
Software Flow Control Select
Single character and dual sequential character software flow control is supported.
Combinations of software flow control can be selected by programming the bits.
EFR[3] EFR[2]
EFR[3]
1
1
0
0
X
X
X
0
1
1
0
0
TABLE 20. EFR (0x2, LCR = 0xBF) (Continued)
R/W
R/W
Def
0
R/W
R/W
R/W
R/W
Def
Def
R/W
R/W
Def
0
0
0
EFR[2]
TABLE 21. Xon1 (0x4, LCR=0xBF)
TABLE 22. Xon2 (0x5, LCR=0xBF)
TABLE 23. Xoff1 (0x6, LCR=0xBF)
TABLE 24. Xoff2 (0x7, LCR=0xBF)
1
0
1
0
X
X
X
0
1
0
1
0
Xoff2 Data
Xon2 Data
Xoff1 Data
EFR[1]
EFR[1]
Xon1 Data
1
1
1
1
1
0
0
0
X
X
X
X
26
EFR[0]
EFR[0]
1
1
1
0
1
0
1
0
X
X
X
X
Description
Rx Flow Control
Rx compares Xon1 & Xon2, Xoff1 & Xoff2
Rx compares Xon1 or Xon2, Xoff1 or Xoff2
Rx compares Xon1 or Xon2, Xoff1 or Xoff2
Rx compares Xon1 & Xon2, Xoff1 & Xoff2
Rx compares Xon1, Xoff1
Rx compares Xon2, Xoff2
No Rx flow control
Tx Flow Control
Tx Xon1 and Xon2, Xoff1 and Xoff2
Tx Xon1, Xoff1
Tx Xon2, Xoff2
No Tx flow control
No Tx & Rx flow control (default)
Description
Description
Description
Description