esa unclassified – for official use npal datasheet f. torelli & p. skrzypek ccsds spring...

ESA UNCLASSIFIED – For Official Use

NPAL Datasheet

F. Torelli & P. SkrzypekCCSDS Spring Meeting 201316/04/2013

NPAL Datasheet | 16/04/2013 | Slide 2

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Contents

• Introduction

• Describing functional interface

• Describing device-specific interface

• Describing packet interface

• Implementing device abstraction control procedure

• Implementing device-specific access protocol

• Summary

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INTRODUCTION

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Introduction

The NPAL device is a multi-function camera with the ability to perform horizon detection and star tracking. The device uses Space Wire link to communicate. The NPAL ICD lists over 23 different data packets.

For the purpose of this presentation, Space Wire has been mapped on SOIS packet service. This presentation is focused on describing packets, SOIS interfaces and access protocols for this device.

Due to the complexity of the device, only a subset of functionality is addressed in this presentation.

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FUNCTIONAL INTERFACE

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Functional interface

Acquire Image

Value ID

Acquire Image,

no arguments

Value

1024x1024 matrix of integer values ranged 0..255

Meta data

bivalent – success or failure

1. <functional_interface>  2.  3.   <interface>  4.     <!-- .. -->  5.     <acquire>  6.       <value_id type="fi_image_acq"/>  7.       <value type="fi_image"/>  8.       <metadata type="fi_bivalent"/>  9.     </acquire>  10.   </interface>  11.   12.   <data_types>  13.     <!-- .. -->  14.     <sequence name="fi_image_acq">  15.       <declare name="header" type="fi_id_header">  16.         <constraint field="id">  17.           <option name="Image"/>  18.         </constraint>  19.       </declare>  20.     </sequence>  21.     <array name="fi_image" type="fi_image_line">  22.       <count const="1024"/>  23.     </array>  24.     <array name="fi_image_line" type="fi_pixel_intensity_t">

  25.       <count const="1024"/>  26.     </array>  27.     <int name="fi_pixel_intensity_t">  28.       <constraints>  29.         <interval>  30.           <left bound="closed" value="0"/>  31.           <right bound="closed" value="255"/>  32.         </interval>  33.       </constraints>  34.     </int>  35.   </data_types>  36. </functional_interface>

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Functional interface

Acquire Temperature

Value ID

Acquire Temperature,

select one of the two thermocouples (APS, Optics)

Value

single float number ranged 0..1.4167911e32

Meta data

bivalent – success or failure

1. <functional_interface>  2.     3.   <interface>  4.     <!-- .. -->  5.     <acquire>  6.       <value_id type="fi_temperature_acq"/>  7.       <value type="fi_temperature"/>  8.       <metadata type="fi_bivalent"/>  9.     </acquire>  10.   </interface>  11.   12.   <data_types>  13.     <!-- .. -->  14.     <sequence name="fi_temperature_acq">  15.       <declare name="header" type="fi_id_header">  16.         <constraint field="id">  17.           <option name="Temperature"/>  18.         </constraint>  19.       </declare>  20.       <declare name="unit" type="fi_thermocouple"/>  21.     </sequence>  22.     <enum name="fi_thermocouple">  23.       <options>  24.         <option name="Optics" value="1"/>  25.         <option name="APS" value="2"/>  26.       </options>  27.     </enum>  28.     <float name="fi_temperature">  29.       <constraints>  30.         <interval>  31.           <left bound="closed" value="0"/>  32.           <right bound="closed" value="1.4167911e32"/>  33.         </interval>  34.       </constraints>  35.     </float>  36.   </data_types>  37. </functional_interface> 

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Functional interface

Command Exposure time

Value ID

Command Exposure time,

no arguments

Value

single float argument ranged 0.050e-3..100.0e-3

Meta data

bivalent – success or failure

1. <functional_interface>  2.    3.   <interface>  4.     <!-- .. -->  5.     <command>  6.       <value_id type="fi_exposure_cmd"/>  7.       <value type="fi_exposure"/>  8.       <metadata type="fi_bivalent"/>  9.     </command>  10.   </interface>  11.   12.   <data_types>  13.     <!-- .. -->  14.     <sequence name="fi_exposure_cmd">  15.       <declare name="header" type="fi_id_header">  16.         <constraint field="id">  17.           <option name="Exposure time"/>  18.         </constraint>  19.       </declare>  20.     </sequence>  21.     <float name="fi_exposure">  22.       <constraints>  23.         <interval>  24.           <left bound="closed" value="0.000050"/>  25.           <right bound="closed" value="0.100000"/>  26.         </interval>  27.       </constraints>  28.     </float>  29.   </data_types>  30. </functional_interface>  

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DEVICE-SPECIFIC INTERFACE

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1. <device_specific_interface>  2.     3.   <interface>  4.     <!-- .. -->  5.     <acquire>  6.       <value_id type="di_image_acq"/>  7.       <value type="di_image"/>  8.       <metadata type="di_bivalent"/>  9.     </acquire>  10.   </interface>  11.   12.   <data_types>  13.     <!-- .. -->  14.     <sequence name="di_image_acq">  15.       <declare name="header" type="di_id_header">  16.         <constraint field="id">  17.           <option name="Image"/>  18.         </constraint>  19.       </declare>  20.     </sequence>  21.     <array name="di_image" type="di_image_line">  22.       <count const="1024"/>  23.     </array>  24.     <array name="di_image_line" type="di_pixel_intensity">  25.       <count const="1024"/>  26.     </array>  27.     <int name="di_pixel_intensity">  28.       <constraints>  29.         <interval>  30.           <left bound="closed" value="0"/>  31.           <right bound="closed" value="255"/>  32.         </interval>  33.       </constraints>  34.     </int>  35.   </data_types>  36. </device_specific_interface>  

Device-specific interface

Acquire Image

Value ID

Acquire Image,

no arguments

Value

1024x1024 matrix of integer values ranged 0..255

Meta data

bivalent – success or failure

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Device-specific interface

Acquire Temperature

Value ID

Acquire Temperature,

select one of the two thermocouples (APS, Optics)

Value

single integer number ranged 0..65535

Meta data

bivalent – success or failure

1. <device_specific_interface>  2.    3.   <interface>  4.     <!-- .. -->  5.     <acquire>  6.       <value_id type="di_temperature_acq"/>  7.       <value type="di_temperature"/>  8.       <metadata type="di_bivalent"/>  9.     </acquire>  10.   </interface>  11.   12.   <data_types>  13.     <!-- .. -->  14.     <sequence name="di_temperature_acq">  15.       <declare name="header" type="di_id_header">  16.         <constraint field="id">  17.           <option name="Temperature"/>  18.         </constraint>  19.       </declare>  20.       <declare name="unit" type="di_thermocouple"/>  21.     </sequence>  22.     <enum name="di_thermocouple">  23.       <options>  24.         <option name="Optics" value="1"/>  25.         <option name="APS" value="2"/>  26.       </options>  27.     </enum>  28.     <int name="di_temperature">  29.       <constraints>  30.         <interval>  31.           <left bound="closed" value="0"/>  32.           <right bound="closed" value="65535"/>  33.         </interval>  34.       </constraints>  35.     </int>  36.   </data_types>  37. </device_specific_interface >

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Device-specific interface

Command Exposure time

Value ID

Command Exposure time,

no arguments

Value

single value from enumeration type

Meta data

bivalent – success or failure

1. <device_specific_interface>  2.    3.   <interface>  4.     <!-- .. -->  5.     <command>  6.       <value_id type="di_exposure_cmd"/>  7.       <value type="di_exposure"/>  8.       <metadata type="di_bivalent"/>  9.     </command>  10.   </interface>  11.   12.   <data_types>  13.     <!-- .. -->  14.     <sequence name="di_exposure_cmd">  15.       <declare name="header" type="di_id_header">  16.         <constraint field="id">  17.           <option name="Exposure time"/>  18.         </constraint>  19.       </declare>  20.     </sequence>  21.     <enum name="di_exposure">  22.       <options>  23.         <option name="0.069ms" value="0"/>  24.         <option name="0.082ms" value="1"/>  25.         <!-- .. -->  26.         <option name="84.10ms" value="41"/>  27.         <option name="100.0ms" value="42"/>  28.       </options>  29.     </enum>  30.   </data_types>  31. </device_specific_interface> 

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Device-specific interface

Command Link speed

Value ID

Command Link speed,

no arguments

Value

single value from enumeration type

Meta data

bivalent – success or failure

1. <device_specific_interface>  2.     3.   <interface>  4.     <!-- .. -->  5.     <command>  6.       <value_id type="di_speed_cmd"/>  7.       <value type="di_speed"/>  8.       <metadata type="di_bivalent"/>  9.     </command>  10.   </interface>  11.   12.   <data_types>  13.     <!-- .. -->  14.     <sequence name="di_speed_cmd">  15.       <declare name="header" type="di_id_header">  16.         <constraint field="id">  17.           <option name="Set speed"/>  18.         </constraint>  19.       </declare>  20.     </sequence>  21.     <enum name="di_speed">  22.       <options>  23.         <option name="100 Mbps" value="0"/>  24.         <option name="50 Mbps" value="1"/>  25.         <option name="25 Mbps" value="2"/>  26.         <option name="16.7 Mbps" value="3"/>  27.         <option name="12.5 Mbps" value="4"/>  28.         <option name="10 Mbps" value="5"/>  29.       </options>  30.     </enum>  31.   </data_types>  32. </device_specific_interface> 

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PACKET INTERFACE

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Packet interface

TC_TRK

1. <packet_interface>  2.   3.   <interface>  4.     <!-- .. -->  5.     <packet>  6.       <data type="pi_tc_trk"/>  7.     </packet>  8.   </interface>  9.   10.   <data_types>  11.     <!-- .. -->  12.     <sequence name="pi_tc_trk">  13.       <declare name="header" type="pi_tc_header">  14.         <constraint field="data_header">  15.           <constraint field="service_type">  16.             <const value="4"/>  17.           </constraint>  18.         </constraint>  19.       </declare>  20.       <declare name="window_start_row" type="pi_pixel_coord"

/>  21.       <declare name="window_start_column" type="pi_pixel_coo

rd"/>22.       <declare name="commanded_exposure_time"   23.                type="pi_exposure_time"/>  24.       <declare name="tracking_option" type="pi_tracking_opti

on"/>25.       <declare name="footer" type="pi_tc_footer"/>  26.     </sequence>  27.   </data_types>  28. </packet_interface> 

Telecommand header

1 Window start row, bits 0-7

2 Window start row, bits 8-15

3 Window start column, bits 0-7

4 Window start column, bits 8-15

5 Commanded exposure time

6 Tracking option

Telecommand footer

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Packet interface

TM_REPORT

1. <packet_interface>  2.   3.   <interface>  4.     <!-- .. -->  5.     <packet>  6.       <data type="pi_tm_report"/>  7.     </packet>  8.   </interface>  9.   10.   <data_types>  11.     <!-- .. -->  12.     <sequence name="pi_tm_report">  13.       <declare name="header" type="pi_tm_header">  14.         <constraint field="data_header">  15.           <constraint field="service_type">  16.             <const value="3"/>  17.           </constraint>  18.         </constraint>  19.       </declare>  20.       <declare name="event_code" type="pi_event_code"/>  21.       <declare name="tc_acceptance" type="pi_tc_acceptance"/

>  22.       <declare name="previous_mode" type="pi_mode"/>  23.       <declare name="current_mode" type="pi_mode"/>  24.       <declare name="cause_of_mode_transition"   25.                type="pi_mode_transition_cause"/>  26.       <declare name="download_status" type="pi_download_stat

us"/>27.       <declare name="not_used" type="pi_fill8"/>  28.       <declare name="calibration" type="pi_calibration_statu

s"/>29.       <declare name="error_code" type="pi_error_code"/>  30.       <declare name="fill1" type="pi_fill8"/>  31.       <declare name="fill2" type="pi_fill8"/>  32.       <declare name="fill3" type="pi_fill8"/>  33.       <declare name="footer" type="pi_tm_footer"/>  34.     </sequence>  35.   </data_types>  36. </packet_interface>  

Telemetry header

1 Event code

2 TC acceptance

3 Mode transition

4 Download status

5 Not used

6 Calibration

7 Error code

8 Fill byte

9 Fill byte

10 Fill byte

Telemetry footer

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DEVICE ABSTRACTION CONTROL PROCEDURE

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Acquire Temperature

1. <device_abstraction_control_procedure>  2.   <!-- .. -->  3.   <request_handler>  4.          5.     <variables>  6.       <declare name="dvs_id" type="fi_temperature_acq"/>  7.       <declare name="das_id" type="di_temperature_acq"/>  8.       <declare name="temperature_raw" type="di_temperature"/

>  9.       <declare name="temperature_kelvin" type="fi_temperatur

e"/>10.       <declare name="dvs_meta" type="fi_bivalent"/>  11.       <declare name="das_meta" type="di_bicalent"/>  12.     </variables>  13.   14.     <value_id>  15.        <variable name="dvs_id"/>  16.     </value_id>  17.   18.     <value>  19.       <variable name="temperature_kelvin"/>  20.     </value>  21.   22.     <metadata>  23.       <variable name="dvs_meta"/>  24.     </metadata>  25.   26.     <process>  27.       <!-- see next slide -->  28.     </process>  29.   30.   </request_handler>  31. </device_abstraction_control_procedure>  

The following code attaches a process to the functional interface. This process will be executed each time the system receives ACQUIRE_FROM_DEVICE primitive with value_id matching fi_temperature_acq.

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Acquire Temperature

dvs_id.unit = APS

dvs_id.unit = OpticsN

das_id.unit := APS das_id.unit := Optics

Y Y

DAS.ACQUIRE_FROM_DEVICE.requestvalue_id <= das_idvalue <= temperature_rawmetadata <= das_metatimeout <= das_timeout

.indication received in time

Y

N

das_meta = success

dvs_meta := failure

dvs_meta := failure

linear_calibrationslope <= 1bias <= -100input <= temperature_rawoutput <= temperature_kelvin

dvs_meta := success

YN

START

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Acquire Temperature

1. <compare>  2.   <subject>  3.     <variable name="dvs_id"> <variable name="unit"/> </variable>  4.   <subject>  5.   <equal>  6.     <reference>  7.       <const value="APS"/>  8.     </reference>  9.     <process>  10.       <copy>  11.         <destination>  12.           <variable name="das_id"/><variable name="unit"/></

variable>13.         </destination>  14.         <source>  15.           <const value="APS"/>  16.         </source>  17.       </copy>  18.     </process>  19.   </equal>  20.   <equal>  21.     <reference>  22.       <const value="Optics"/>  23.     </reference>  24.     <process>  25.       <copy>  26.         <destination>  27.           <variable name="das_id"/><variable name="unit"/></

variable>  28.         </destination>  29.         <source>  30.           <const value="Optics"/>  31.         </source>  32.       </copy>  33.     </process>  34.   </equal>  35. </compare>  

dvs_id.unit = APS

dvs_id.unit = OpticsN

das_id.unit := APS das_id.unit := Optics

Y Y

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Acquire Temperature

1. <das_acquire>  2. 3.   <value_id>  4.     <variable name="das_id"/>  5.   </value_id> 6.  7.   <value>  8.     <variable name="temperature_raw"/>  9.   </value>  10. 11.   <metadata>  12.     <variable name="das_meta"/>  13.   </metadata> 14.  15.   <time_limit>  16.     <alias name="das_timeout"/>  17.   </time_limit>  18. 19.   <on_success>  20.     <!-- see next slide -->  21.   </on_success>  22. 23.   <on_timeout>  24.     <!-- see next slide -->  25.   </on_timeout>  26. 27. </das_acquire> 

DAS.ACQUIRE_FROM_DEVICE.requestvalue_id <= das_idvalue <= temperature_rawmetadata <= das_metatimeout <= das_timeout

.indication received in timeY N

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Acquire Temperature

1. <compare>  2.   <subject>  3.     <variable name="das_meta"/>  4.   </subject>  5.   <reference>  6.     <const value="success"/>  7.   </reference>  8.   <equal>  9.     <linear_calibration>  10.      <slope> <const value="1"/> </slope>  11.      <bias> <const value="-100"/> </bias>  12.      <input> <variable name="temperature_raw"/> </input>  13.      <output> <variable name="temperature_kelvin"/> </output>  14.    </linear_calibration>  15.    <copy>  16.      <destination>  17.        <variable name="dvs_meta"/>  18.      </destination>  19.      <source>  20.        <const value="success"/>  21.      </source>  22.    </copy>  23.  </equal>  24.  <not_equal>  25.    <copy>  26.      <destination>  27.        <variable name="dvs_meta"/>  28.      </destination>  29.      <source>  30.        <const value="failure"/>  31.      </source>  32.    </copy>  33.  </not_equal>  34.</compare> 

1. <copy>  2.   <destination>  3.     <variable name="dvs_meta"/>  4.   </destination>  5.   <source>  6.     <const value="failure"/>  7.   </source>  8. </copy>  

das_meta = success

dvs_meta := failure

dvs_meta := failure

linear_calibrationslope <= 1bias <= -100input <= temperature_rawoutput <= temperature_kelvin

dvs_meta := success

Y N

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DEVICE-SPECIFIC ACCESS PROTOCOL

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Command Exposure time

1. <device_specific_access_protocol>  2.   <!-- .. -->  3.   <request_handler> 4.  5.     <variables>  6.       <declare name="id" type="di_exposure_cmd"/>  7.       <declare name="data" type="di_exposure"/>  8.       <declare name="meta" type="di_bivalent"/>  9.       <declare name="trk_packet" type="pi_tc_trk"/>  10.       <declare name="report_packet" type="pi_tm_report"/>  11.     </variables>  12. 13.     <value_id>  14.       <variable name="id"/>  15.     </value_id>  16. 17.     <value>  18.       <variable name="data"/>  19.     </value>  20. 21.     <metadata>  22.       <variable name="meta"/>  23.     </metadata> 24.  25.     <process>  26.       <!-- see next slides -->  27.     </process>  28. 29.   </request_handler>  30. </device_specific_access_protocol> 

The following code attaches a process to the device-specific interface. This process will be executed each time the system receives COMMAND_DEVICE primitive with value_id matching di_exposure_cmd.

NPAL Datasheet | 16/04/2013 | Slide 25

ESA UNCLASSIFIED – For Official Use

Command Exposure time

trk_packet.window_start_row := 0trk_packet.window_start_column := 0trk_packet.tracking_option := normal

data = 0.069ms

data = 0.082ms

data = 84.10ms

data = 100.0ms

PS.PACKET_SEND.requestdestination_address <= npal_addrdata <= trk_packet

wait for PS.PACKET.RECEIVE.indicationsource_address <= npal_addrdata <= report_packettimeout <= npal_timeout

packet received in time

meta := failure

meta := failure

report_packet.tc_acceptance = accepted

meta := success

trk_packet.commanded_exposure_time := 0.069ms

trk_packet.commanded_exposure_time := 0.082ms

trk_packet.commanded_exposure_time := 84.10ms

trk_packet.commanded_exposure_time := 100.0msY

N

Y

N

Y

N

Y

N

NY

NY

START

...

NPAL Datasheet | 16/04/2013 | Slide 26

ESA UNCLASSIFIED – For Official Use

Command Exposure time

1. <copy>  2.   <destination>  3.     <variable name="trk_packet"/>  4.       <variable name="window_start_row"/>  5.     </variable>  6.   </destination>  7.   <source>  8.     <const value="0"/>  9.   </source>  10. </copy>  11. <copy>  12.   <destination>  13.     <variable name="trk_packet"/>  14.       <variable name="window_start_column"/>  15.     </variable>  16.   </destination>  17.   <source>  18.     <const value="0"/>  19.   </source>  20. </copy>  21. <copy>  22.   <destination>  23.     <variable name="trk_packet"/>  24.       <variable name="tracking_option"/>  25.     </variable>  26.   </destination>  27.   <source>  28.     <const value="normal"/>  29.   </source>  30. </copy> 

trk_packet.window_start_row := 0

trk_packet.window_start_column := 0

trk_packet.tracking_option := normal

NPAL Datasheet | 16/04/2013 | Slide 27

ESA UNCLASSIFIED – For Official Use

Command Exposure time

1. <compare>  2.   <subject>  3.     <variable name="data"/>  4.   </subject>  5.   <equal>  6.     <reference>  7.       <const value="0.069ms">  8.     </reference>  9.     <process>  10.       <copy>  11.         <destination>  12.           <variable name="trk_packet">  13.             <variable name="commanded_exposure_time"/>  14.           </variable>  15.         </destination>  16.         <source>  17.           <const value="0.069ms"/>  18.         </source>  19.       </copy>  20.     </process>  21.   </equal>  22.   <equal>  23.     <reference>  24.       <const value="0.082ms">  25.     </reference>  26.     <process>  27.       <copy>  28.         <destination>  29.           <variable name="trk_packet">  30.             <variable name="commanded_exposure_time"/>  31.           </variable>  32.         </destination>  33.         <source>  34.           <const value="0.082ms"/>  35.         </source>  36.       </copy>  37.     </process>  38.   </equal>

data = 0.069ms

data = 0.082ms

trk_packet.commanded_exposure_time := 0.069ms

trk_packet.commanded_exposure_time := 0.082ms

Y

N

Y

N

NPAL Datasheet | 16/04/2013 | Slide 28

ESA UNCLASSIFIED – For Official Use

Command Exposure time

1.   <equal>  2.     <reference>  3.       <const value="84.10ms">  4.     </reference>  5.     <process>  6.       <copy>  7.         <destination>  8.           <variable name="trk_packet">  9.             <variable name="commanded_exposure_time"/>  10.           </variable>  11.         </destination>  12.         <source>  13.           <const value="84.10ms"/>  14.         </source>  15.       </copy>  16.     </process>  17.   </equal>  18.   <equal>  19.     <reference>  20.       <const value="100.0ms">  21.     </reference>  22.     <process>  23.       <copy>  24.         <destination>  25.           <variable name="trk_packet">  26.             <variable name="commanded_exposure_time"/>  27.           </variable>  28.         </destination>  29.         <source>  30.           <const value="100.0ms"/>  31.         </source>  32.       </copy>  33.     </process>  34.   </equal>  35. </compare>

data = 84.10ms

data = 100.0ms

trk_packet.commanded_exposure_time := 84.10ms

trk_packet.commanded_exposure_time := 100.0ms

Y

N

Y

N

NPAL Datasheet | 16/04/2013 | Slide 29

ESA UNCLASSIFIED – For Official Use

Command Exposure time

1. <packet_send>  2.   <destination_address>  3.     <alias name="npal_addr"/>  4.   </destination_address>  5.   <data>  6.     <variable name="trk_packet"/>  7.   </data>  8. </packet_send>  9. <wait_for_packets>  10.   <scenario>  11.     <minterm>  12.       <packet_receive>  13.         <source_address>  14.           <alias name="npal_addr"/>  15.         </source_address>  16.         <data>  17.           <variable name="report_packet"/>  18.         </data>  19.       </packet_receive>  20.     </minterm>  21.     <process>  22.       <!-- see next slide -->  23.     </process>  24.   </scenario>  25.   <timeout>  26.     <time_limit>  27.       <alias name="npal_timeout"/>  28.     </time_limit>  29.     <process>  30.       <!-- see next slide -->  31.     </process>  32.   </timeout>  33. </wait_for_packets> 

PS.PACKET_SEND.requestdestination_address <= npal_addrdata <= trk_packet

wait for PS.PACKET.RECEIVE.indicationsource_address <= npal_addrdata <= report_packettimeout <= npal_timeout

NPAL Datasheet | 16/04/2013 | Slide 30

ESA UNCLASSIFIED – For Official Use

Command Exposure time

1. <compare>  2.   <subject>  3.     <variable name="report_packet">  4.       <variable name="tc_acceptance"/>  5.     </variable>  6.   </subject>  7.   <reference>  8.     <const value="accepted"/>  9.   </reference>  10.   <equal>  11.     <copy>  12.       <destination>  13.         <variable name="meta"/>  14.       </destination>  15.       <source>  16.         <const value="success"/>  17.       </source>  18.     </copy>  19.   </equal>  20.   <not_equal>  21.     <copy>  22.       <destination>  23.         <variable name="meta"/>  24.       </destination>  25.       <source>  26.         <const value="failure"/>  27.       </source>  28.     </copy>  29.   </not_equal>  30. </compare>  

1. <copy>  2.   <destination>  3.     <variable name="meta"/

>  4.   </destination>  5.   <source>  6.     <const value="failure"/

>  7.   </source>  8. </copy>  

packet received in time

meta := failure

meta := failure

Report_packet.tc_acceptance = accepted

meta := success

NY

NY

NPAL Datasheet | 16/04/2013 | Slide 31

ESA UNCLASSIFIED – For Official Use

SUMMARY

NPAL Datasheet | 16/04/2013 | Slide 32

ESA UNCLASSIFIED – For Official Use

Summary

• Described sample SOIS functional interface and device-specific interface

• Described 2 NPAL packets available from SOIS subnetwork

• Implemented one process of the device-specific access protocol

• Implemented one process of the device abstraction control procedure

• The attached XML document contains description of all NPAL packets

and all sample SOIS interfaces

• Attached EDS may not be perfectly cnsistent. Back-propagating all

updates to the EDS schema is very time consuming.