CfsPacketPreprocessor (Yamcs :: Core 5.3.2 API)

java.lang.Object
- org.yamcs.tctm.AbstractPacketPreprocessor
- - org.yamcs.tctm.cfs.CfsPacketPreprocessor

All Implemented Interfaces:

PacketPreprocessor
```
public class CfsPacketPreprocessor
extends AbstractPacketPreprocessor
```
Preprocessor for the CFS TM packets:
- CCSDS primary header 6 bytes
- Time seconds 4 bytes
- subseconds(1/2^16 fraction of seconds) 2 bytes
Options:
```
   dataLinks:
   ...
      packetPreprocessor: org.yamcs.tctm.cfs.CfsPacketPreprocessor
      packetPreprocessorArgs:
          byteOrder: LITTLE_ENDIAN
          timeEncoding:
              epoch: CUSTOM
              epochUTC: 1970-01-01T00:00:00Z
              timeIncludesLeapSeconds: false
 
 
```
The byteOrder option (default is BIG_ENDIAN) is used only for decoding the timestamp in the secondary header: the 4 bytes second and 2 bytes subseconds are decoded in little endian.
The primary CCSDS header is always decoded as BIG_ENDIAN.
For explanation on the timeEncoding property, please see AbstractPacketPreprocessor. The default timeEncoding used if none is specified, is GPS, equivalent with this configuration:
```
 timeEncoding:
     epoch: GPS
 
```
which is also equivalent with this more detailed configuration:
```
 timeEncoding:
     epoch: CUSTOM
     epochUTC: "1980-01-06T00:00:00Z"
     timeIncludesLeapSeconds: true
 
```

Nested Class Summary
- Nested classes/interfaces inherited from class org.yamcs.tctm.AbstractPacketPreprocessor
  AbstractPacketPreprocessor.TimeEpochs

Field Summary
- Fields inherited from class org.yamcs.tctm.AbstractPacketPreprocessor
  byteOrder, CONFIG_KEY_ERROR_DETECTION, CONFIG_KEY_TCO_SERVICE, CONFIG_KEY_TIME_ENCODING, customEpoch, customEpochIncludeLeapSecond, errorDetectionCalculator, eventProducer, log, tcoService, timeDecoder, timeEpoch, timeService, useLocalGenerationTime

Constructor Summary

Constructors
Constructor Description

CfsPacketPreprocessor(String yamcsInstance)

CfsPacketPreprocessor(String yamcsInstance, YConfiguration config)

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`boolean`	`checkForSequenceDiscontinuity()`
`void`	`checkForSequenceDiscontinuity(boolean checkForSequenceDiscontinuity)`	The packet preprocessor processes multiple packets that should be in sequence.
`TmPacket`	`process(TmPacket pkt)`	Processes the packet and returns it.

Methods inherited from class org.yamcs.tctm.AbstractPacketPreprocessor
getErrorDetectionWordCalculator, shiftFromEpoch

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface org.yamcs.tctm.PacketPreprocessor
process

- Constructor Detail
  - CfsPacketPreprocessor
```
public CfsPacketPreprocessor(String yamcsInstance)
```
  - CfsPacketPreprocessor
```
public CfsPacketPreprocessor(String yamcsInstance,
                             YConfiguration config)
```
- Method Detail
  - process
```
public TmPacket process(TmPacket pkt)
```
    Description copied from interface: PacketPreprocessor
    
    Processes the packet and returns it.
    What this function does is project depended. However, we expect that the generation time and sequence count are filled in.
    Can return null if the packet is to be ignored.
    
    Parameters:
    
    pkt - - the packet that has to be processed
    
    Returns:
    
    the processed packet
  - checkForSequenceDiscontinuity
```
public boolean checkForSequenceDiscontinuity()
```
  - checkForSequenceDiscontinuity
```
public void checkForSequenceDiscontinuity(boolean checkForSequenceDiscontinuity)
```
    Description copied from interface: PacketPreprocessor
    
    The packet preprocessor processes multiple packets that should be in sequence. This flag can be used to check that indeed the packets are in sequence and produce a warning otherwise.