XR68C192 Datasheet, PDF (17/32 Pages) Exar Corporation – DUAL UNIVERSAL ASYNCHRONOUS RECEIVER AND TRANSMITTER

XR68C92/192
MR0 A/B
Mode register 0. This register is accessed only when
command is applied via CR A/B register. After reading
or writing to MR0 A/B register, the pointer will point to
MR1 A/B register.
MR0 A/B Bit-0.
Extended baud rate table selection.
0 = Normal baud rate tables
1 = Extend baud rate tables (1)
MR0 A/B Bit-1.
0 = Regular Operation
1 = Factory test mode
MR0 A/B Bit-2.
Extended baud rate table selection.
0 = Normal baud rate tables
1 = Extend baud rate tables (2)
MR0 A/B Bit-3.
Not used.
MR0 A/B Bits 5-4
Transmit trigger levels:
MR0
Bit-5
0
0
1
1
MR0
Bit-4
0
1
0
1
XR68C92
8 FIFO locations empty
4 FIFO locations empty
6 FIFO locations empty
1 FIFO location empty
MR0
Bit-5
0
0
1
1
MR0
Bit-4
0
1
0
1
XR68C192
16 FIFO locations empty
6 FIFO locations empty
12 FIFO locations empty
1 FIFO location empty
MR0 A/B Bit-6.
Receive trigger levels:
MR0
Bit-6
0
0
1
1
MR1
Bit-6
0
1
0
1
XR68C92
1 byte in FIFO
3 bytes in FIFO
6 bytes in FIFO
8 bytes in FIFO
MR0
Bit-6
MR1
Bit-6
XR68C192
0
0
1 byte in FIFO
0
1
6 bytes in FIFO
1
0
12 bytes in FIFO
1
1
16 bytes in FIFO
MR0 A/B Bit-7.
Receive time-out (watch dog timer).
0 = Disabled
1 = Enabled
MR1 A/B
Mode register 1. MR1 A/B are accessed after reset or
by command applied via CR A/B register. After read-
ing or writing to MR1 A/B register, the pointer will point
to MR2 A/B register.
MR1 A/B Bits 1-0.
Character Length
00=5
01=6
10=7
11=8
MR1 A/B Bit-2.
Parity Type
0 = Even Parity
1 = Odd Parity
MR1 A/B Bit 4-3.
Parity mode
00 = With parity
01 = Force parity
10 = No parity
11 = Multidrop mode
MR1 A/B Bit-5.
Data error mode
0 = Single Character mode
1 = Block (FIFO) mode
MR1 A/B Bit-6.
Receive Interrupt mode select.
0 = Single character mode (RxRdy)
1 = FIFO Full mode (FFULL)
MR1 A/B Bit-7.
Auto RTS flow control.
Rev. P1.10
17