XR16L784_05 Datasheet, PDF (23/52 Pages) Exar Corporation – HIGH PERFORMANCE 2.97V TO 5.5V QUAD UART

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REV. 1.2.2
XR16L784
HIGH PERFORMANCE 2.97V TO 5.5V QUAD UART
TIMERCNTL Register
Bit-7 Bit-6 Bit-5 Bit-4 Bit-3 Bit-2 Bit-1 Bit-0
Rsvd
Rsvd Rsvd
Rsvd
Clock Single/ Start/ INT
Select Re-trigger Stop Enable
TIMER [7:0] (default 0x00): Reserved.
TIMERMSB [7:0] and TIMERLSB [7:0]
TIMERMSB and TIMERLSB form a 16-bit value. The least-significant bit of the timer is being bit [0] of the
TIMERLSB with most-significant-bit being bit [7] in TIMERMSB. Reading the TIMERCNTL register will clear its
interrupt. Default value is zero upon powerup and reset.
16-Bit Timer/Counter Programmable Registers
TIMERMSB Register
TIMERLSB Register
Bit-15 Bit-14 Bit-13 Bit-12 Bit-11 Bit-10 Bit-9 Bit-8
Bit-7 Bit-6 Bit-5 Bit-4 Bit-3 Bit-2 Bit-1 Bit-0
3.1.3 8XMODE [7:0] (default 0x00)
Each bit selects 8X or 16X sampling rate for that UART channel, bit-0 is channel 0. Logic 0 (default) selects
normal 16X sampling with logic one selects 8X sampling rate. Transmit and receive data rates will double by
selecting 8X.
8XMODE Register
Individual UART Channel 8X Clock Mode Enable
Bit-7 Bit-6 Bit-5 Bit-4 Bit-3 Bit-2 Bit-1 Bit-0
Rsvd Rsvd Rsvd Rsvd Ch-3 Ch-2 Ch-1 Ch-0
3.1.4
3.1.5
REGA [7:0] reserved (default 0x00)
RESET [7:0] (default 0x00)
RESET Register
Individual UART Channel Reset Enable
Bit-7 Bit-6 Bit-5 Bit-4 Bit-3 Bit-2 Bit-1 Bit-0
Rsvd Rsvd Rsvd Rsvd Ch-3 Ch-2 Ch-1 Ch-0
The 8-bit Reset register [RESET] provides the software with the ability to reset individual UART(s) when there
is a need. Each bit is self-resetting after it is written a logic 1 to perform a reset to that channel. All registers in
that channel will be reset to the default condition, see Table 19 for details. As an example, bit-0 =1 resets
UART channel 0 with bit-3=1 resets channel 3.
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