SSCI HSS4NG, User Manual, Page: 19 / 34

CCII/HSS8/6-MAN/004 2009-08-31 Issue 1.2
CH8MAN04.WPD
Page 11 of 26
5.4.1 UART Protocol Information
Name Options Description
Baud Rate
1 200 - 1 Mbit/s (RS-232)
1 200 - 16 Mbit/s (RS-422/485)
Any values permissible.
The equation to calculate the actual baud rate for asynchronous
UART is as follows :
Actual baud rate = 100 MHz / 16 / ROUND (100 MHz / 16 /
Desired baud rate)
The equation to calculate the actual baud rate for synchronous
UART is as follows :
Actual baud rate = 100 MHz / ROUND (100 MHz / Desired
baud rate)
Where ROUND () implies that the result is rounded to the nearest
integer.
Used to specify a single baud rate
for both transmitter and receiver.
Units in bit/s.
Clock Source CLOCK_DEFAULT CLOCK_DEFAULT connects Baud
Rate Generators (BRGs) [1 - 4] to
Ports [1 - 4] and Ports [5 - 8].
For synchronous UART :
When transmit clock is set to
CLOCK_BRG[1-4], then receive
clock is still set to CLOCK_EXT[1-4]
for Ports [1 - 4] and Ports [5 - 8].
For asynchronous UART :
Transmit and receive clocks can be
set to one of CLOCK_BRG[1-4] or
CLOCK_EXT[1-4].
Note :
There are four BRGs and four clock
input pins per PowerQUICC II
processor.
CLOCK_BRG1
CLOCK_BRG2
CLOCK_BRG3
CLOCK_BRG4 BRGs [1 - 4]
BRG1 for Ports [1 and 5].
BRG2 for Ports [2 and 6].
BRG3 for Ports [3 and 7].
BRG4 for Ports [4 and 8].
CLOCK_EXT1
CLOCK_EXT2
CLOCK_EXT3
CLOCK_EXT4 External Clocks connected
on CLK_IN pins.
Note :
CLOCK_EXT[1-2] can only
be used for Ports [1 and 2]
and [5 and 6], while
CLOCK_EXT[3-4] can only
be used for Ports [3 and 4]
and [7 and 8].
Async. Flow Control Normal or asynchronous flow
control.
Stop bits
ONE
TWO Number of full stop bits.
Data Bits
5
6
7
8
9
10
11
12
13
14 Number of data bits. Note only
Ports [9-12] support nine or more
data bits.
UART Mode NORMAL
MAN MM
AUTO MM Select UART mode :
Normal, manual multidrop or
automatic multidrop mode.