M88 Evaluation Kit User Guide
Using the PLL
STO-DEV7227-HB Rev. 2.1
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Using the PLL
In the same way that the PTP engine can be configured using the
ptp2
set of commands, there are many
possibilities of configuring the onboard PLL functionality using the
pll
set of commands. Here’s a general
description of these commands. For brief information of the various commands, type
pll
help in the
console. For more detailed information, we refer to [1].
15.1
Configuration
Similar to the PTP engine, some parameters need to be configured in advance, in the sense that all
modifications to the configuration are stored in memory and will only take effect after they are loaded
into the PLL (see section 15.2). There are three sections that needs to be configured: Inputs, DSPLLs and
Outputs. The currently loaded configuration can be shown using the command
pll config print
.
15.1.1
Configure inputs
Usage: pll config input <inpin_num> <command> [parameters]
Configure the input frequency for the specified input or disable/enable the specified input.
15.1.2
Configure DSPLL
Usage: pll config dspll <dspll_num> <command> [parameters]
Configure what input should feed the DSPLL, any selection method, the frequency plan for the DSPLL
and whether the DSPLL should be controlled by DCO or not.
15.1.3
Configure outputs
Usage: pll config output <outpin_num> <command> [parameters]
Configure which DSPLL should drive the specified output, what frequency the output should have and
whether it’s enabled or disabled.
15.2
Loading
When the configuration is done, this is made effective by the command
pll load current
.
15.3
Controlling
With the PLL running, some parameters can be changed in runtime. This include enabling and disabling
inputs and outputs.
15.3.1
Control input
Usage: pll control input <inpin_num> <command> [parameters]
Enable or disable the specified input.
15.3.2
Control DSPLL
Usage: pll control dspll <dspll_num> <command> [parameters]
Assign a specified input to the specified DSPLL. Only possible if DSPLL is set to manual input selection.
15.3.3
Control Output
Usage: pll control output <outpin_num> <command> [parameters]
Enable or disable the specified output.
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Further configuration of the M88 Evaluation Kit
For details on how to configure and control the PLL section of the M88, see [1].
