Texas Instruments OMAP5912 Reference Manual page 1264

Figure 77. Autobaud State Machine
<CR>
no PE
a
6.6.13 Frame Closing
SPRU760B
!(A⎟ a⎟ t)
a
Wait t
(Baud rate
acquired)
t
A transmission frame is properly terminated in one of two ways:
Frame-length method: The frame-length method is selected when MDR1[7]
-
= 0. The local host writes the frame-length value to the TXFLH and TXFLL
registers. The device automatically attaches end flags to the frame once
the number of bytes transmitted becomes equal to the frame-length value.
Set-EOT bit method: The Set-EOT bit method is selected when MDR1[7]
-
= 1. The local host writes 1 to ACREG[0] (EOT bit) just before it writes the
last byte to the TX FIFO. When the local host writes the last byte to the TX
FIFO, the device internally sets the tag bit for that particular character in
the TX FIFO. As the TX state machine reads data from the TX FIFO, it uses
this tag-bit information to attach end flags and properly terminate the
frame.
!(A⎟ a)
Wait a or A
!(A⎟ a⎟ T)
A
a
(Baud rate
A
acquired)
T
Reception
!<CR>
Wait T
A
Serial Interfaces
UARTs
199