Maps and Registers
ATCA-7360 Installation and Use (6806800J07S)
179
6.3.4.3
Programmable Baud Rate Generator
The UART contains a programmable Baud Rate Generator that is capable of taking the
UART_CLK input and dividing it by any divisor from 1 to (2 16 -1). The output frequency of the
Baud Rate Generator is 16 times the baud rate. Two 8-bit latches store the divisor in a 16-bit
binary format. These Divisor Latches must be loaded during initialization to ensure proper
operation of the Baud Rate Generator. If both Divisor Latches are loaded with 0, the 16X output
clock is stopped. Upon loading either of the Divisor latches, a 16-bit baud counter is
immediately loaded. This prevents long counts on initial load. Access to the Divisor latch can be
done with a word write.
The UART_CLK is the CLK_UART (48MHz) input divided by the pre-divider set by the Super IO
Configuration Register (Offset 0x29).
The baud rate of the data shifted in/out of the UART is given by:
Baud Rate = UART_CLK / (16X Divisor)
For example, if the pre-divider is 26 the UART_CLK is 1.8461538MHz. When the divisor is 12,
the baud rate is 9600.
A Divisor value of 0 in the Divisor Latch Register is not allowed.
6.4
FPGA Register Mapping
Table 6-38 Divisor Latch LSB Register (DLL), if DLAB=1
LPC IO Address: Base
Bit
Description
Default
Access
7:0
Divisor Latch LSB (DLL)
Undef.
LPC: r/w
Table 6-39 Divisor Latch MSB Register (DLM), if DLAB=1
LPC IO Address: Base + 1
Bit
Description
Default
Access
7:0
Divisor Latch MSB (DLM)
Undef.
LPC: r/w
Summary of Contents for ATCA-7360
Page 1: ...ATCA 7360 Installation and Use P N 6806800J07S May 2016...
Page 26: ...ATCA 7360 Installation and Use 6806800J07S About this Manual 26 About this Manual...
Page 36: ...ATCA 7360 Installation and Use 6806800J07S Sicherheitshinweise 36...
Page 43: ...Introduction ATCA 7360 Installation and Use 6806800J07S 43...
Page 44: ...Introduction ATCA 7360 Installation and Use 6806800J07S 44...
Page 66: ...Installation ATCA 7360 Installation and Use 6806800J07S 66...
Page 258: ...Supported IPMI Commands ATCA 7360 Installation and Use 6806800J07S 258...
Page 284: ...Replacing the Battery ATCA 7360 Installation and Use 6806800J07S 284...
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