Configuration manual¶

You may see a fragment of the typical FLOW configuration file below. with basic explanation in comments

XML configuration for SWSYS¶

<swsys>
    <expected_interface name="TLM1" dev_path="/dev/ttyS0"/>

    ...

    <bus name="gcu_bus" eq_channel="0" max_topics="32">
        <event_queue buffer_size="2000" size="32"/>
        <dir name="hk" eq_channel="16"/>
        <dir name="nav" eq_channel="16"/>
        <dir name="cont" eq_channel="16"/>
    </bus>

    <task type="flow" config="flow_nav_imu_alignment.xml" name="nav_imu_alignement" priority="4" clk_method="timer" clk_period="100">
        <connect>
            <in alias="omega, a">nav_bus/$alias</in>
            <out alias="omega_bias, q0, imu_reset">nav_bus/$alias</out>
        </connect>
    </task>

    ...

    <bridge name="nav" priority="2" clk_method="timer" clk_period="50" to="gcu_bus/nav">
        <source alias="omega, a">nav_bus/$alias</source>
        <source alias="roll, pitch, yaw">nav_bus/$alias</source>
    </bridge>

    ...

    <service type="sdtl" name="gcu_link">
        <baudrate value="57600"/>

        <serial_port value="/dev/ttyS0"/>

        <channel id="1" name="downlink" type="rel"/>
        <channel id="2" name="downlink_sk" type="unrel"/>
    </service>

    ...

</swsys>

<expected_interface> mark existing external interfaces¶

This tag does not have any functional support in C-ATOM but used for visualization purposes for now.

<bus> specify software buses for your system¶

<bus name="gcu_bus" eq_channel="1" max_topics="32">
    <event_queue buffer_size="2000" size="32"/>
    <dir name="hk" eq_channel="16"/>
    <dir name="nav" eq_channel="16"/>
    <dir name="cont" eq_channel="16"/>
</bus>

Tag	Attrs	Description
bus		Define ESWB bus in a software system
	name	Name of the bus
	eq_channel	optional attribute to define event queue channel for the whole bus (see Event Queue for details), this number will be inherited by all nested directories and topics
event_queue		Activate event queue for a bus with specified parameters (see Event Queue for details)
	buffer_size	Size of data buffer for all events in a queue
	size	Maximum number of events to contain in a queue
dir		Create a directory in the bus
	name	Name of the directory
	eq_channel	Optional attribute for defining event queue channel number for directory and its content.

<task> define functional computing units¶

<task type="flow" config="flow_nav_imu_alignment.xml" name="nav_imu_alignement" priority="4" clk_method="timer" clk_period="100">
    <connect>
        <in alias="omega, a">nav_bus/$alias</in>
        <out alias="omega_bias, q0, imu_reset">nav_bus/$alias</out>
    </connect>
</task>

<task type="flow" config="flow_cont_angrate.xml" name="cont_angrate" priority="6" clk_method="inp_upd" clk_input_path="nav_bus/omega">
    <connect>
        <in alias="omega">nav_bus/omega</in>
        <in alias="desired_omega">control_bus/desired_omega</in>

        <in alias="arming, direct">control_bus/rc/$alias</in>
        <in alias="collective">control_bus/rc/direct_collective</in>
        <in alias="pids_gain">control_bus/rc/pid_gain_angrate</in>
        <in alias="enable">control_bus/rc/enable_angrate</in>
        <out alias="m1, m2, m3, m4, armed">control_bus/solution/$alias</out>
    </connect>
</task>

Tag	Attrs	Description
task		Define task inside software system
	type	type of the task, these are available: flow, fsm, ibr
	name	name of the task
	config	relative path to configuration file (relative to the catalog with swsys configuration file)
	priority	relative priority against launching thread, usually the default priority, check your OS for valid range
	clk_method	method of execution control of the task over time; these options are available: freerun - task don’t block between cycles; timer - unblock task every specified amount of time (makes clk_period attribute valid); inp_update - clock on input update, unblock task when specified ESWB topic is published (makes clk_input_path attribute valid);
	clk_period	time in milliseconds between task iterations, valid only when clk_method is timer
	clk_input_path	path to the ESWB topic for waiting of hte update, valid only when clk_method is inp_update
connect		Task connection section
in		Specify subscription path/paths for task’s inputs stated in alias attribute(these inputs must be defined in task’s functional specification (see Function specification for details)
	alias	alias or list of input’s aliases separated by comma
out		Specify publishing path/paths for task’s outputs stated in alias attribute(these outputs must be defined in task’s functional specification (see Function specification for details)
	alias	alias or list of output’s aliases separated by comma

<service> place supporting services¶

<service type="sdtl" name="gcu_link">
    <baudrate value="57600"/>

    <serial_port value="/dev/ttyS0"/>

    <channel id="1" name="downlink" type="rel"/>
    <channel id="2" name="downlink_sk" type="unrel"/>
</service>

Tag	Attrs	Description
service	type=”sdtl”	Instantiate Simple Data Transmission Layer (SDTL) service
	name	name of SDTL service instance
baudrate	value	Define baudrate for SDTL instance
serial_port	value	Define define path to the serial port for SDTL service to communicate
channel		Define a SDTL channel, a unit to transfer multiplexed information
	id	Channel identification number, must be within 0-255, unique and correspond with the channels on the recipient’s side
	name	Name of the SDTL channel
	type	protocol type of the SDTL channel; these types are available: rel - reliable data delivery with acknowledgment await; unrel - unreliable data delivery via simplex streaming

<service type="eqrb_sdtl" name="debug_sdtl">
    <event_queue_source value="gcu_bus"/>

    <sdtl_service value="gcu_link"/>

    <channel_1_name value="downlink"/>

    <channel_2_name value="downlink_sk"/>
</service>

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