Wikiadmin: Text replacement - "ice-online.biz" to "ice-online.com"

2020-05-09T19:42:58Z

Text replacement - "ice-online.biz" to "ice-online.com"

Wikiadmin at 16:54, 12 October 2018

2018-10-12T16:54:00Z

Wikiadmin: Created page with "== Packet-based Hardware == * Seven of the 20+ I/O Modules in production are packet-based. * These include FPDP, FPQC, GXD, UDP, SONET, and SONET2. * Systems in the field cur..."

2018-10-12T16:29:18Z

Created page with "== Packet-based Hardware == * Seven of the 20+ I/O Modules in production are packet-based. * These include FPDP, FPQC, GXD, UDP, SONET, and SONET2. * Systems in the field cur..."

New page

== Packet-based Hardware ==
* Seven of the 20+ I/O Modules in production are packet-based.
* These include FPDP, FPQC, GXD, UDP, SONET, and SONET2.
* Systems in the field currently capturing 80Mby/sec to disk from SONET and UDP modules.
* [[ICE-PIC4|PIC4X]] and [[ICE-PIC5|PIC5]] have packet-based 800Mby/sec hyper-transport links to processor module sites.
* The [[DTDM]] can wide band resample, tune from 32 to 3000 channels, and demodulate all tuner outputs.
* On processing modules, each DSP library call (TFD,FFT,DEMOD) is a packet.
* Tuner chips run at 101MHz. Input FIFO handles oversampling and/or burst data (graychip time-outs)

== Packet-based Software ==
* Packets in NeXtMidas I/O libraries are handled by a packet handler interface
* Handlers for ICE, RMIF, and SDDS packet types have been implemented in the ICE tree.
* X-Midas 380 also supports packets
* SOURCEPIC/PACKET creates ICE packets for ELCCP processor and others
* PICFUNC allows packing/unpacking multiple channels with optional strip of packet headers
* COGS uses separate file of packet headers to index into single packet data file.
* Archiving to one large packetized file is more efficient that many small files

== ICE Packets ==
* Header is fixed 64 bytes starting with a 4-byte key.
* Data size is contained in the header, but is usually fixed at a nominal transfer length.
* Midas file is type=1000 format=any with PACKET=ICE keyword in main header.
* ICE packets have 2 double precision time fields, and one double precision sample offset
* Allows late determination of sample delta, (need this option in X-Midas packets)

{{pagebreak}}

== SDDS Packets ==
* Header is fixed 56 bytes with no key. Data is 1024 bytes. See [[Media:SDDSPacket.doc|SDDSPacket.doc]]
* Midas file is type 1000, format=SB|SI with PACKET=SDDS keyword in main header.
* Theoretical max data throughput is 111Mby/sec. Raw 125Mby/sec less overhead (gap=1%, ether=5.5%, sdds=5.5%)
* ICE-UDP Module FPGA code adds 8 bytes in front with 2-byte key, source port and IP address.
* The resulting [[ICE_Help_GENERAL#PACKETS - Packet data formats and handlers|64 byte header]] includes essential routing/channel info and keeps accesses on cache lines.
* Gate array code in the PIC4T/MBT4 interprets timecode field and optionally strips off header.
* Use /TC=SDDS for raw or tuner data just as with SDN, SMS, CPU, IRIGB, etc.
* Switch routing through: MidasPrompt> PICD SET <MODxx> IPCONN <address>
* Initial testing using white noise test file from SDDS hardware, played back via NeXtMidas.
* Screen shots of packet test through [[Communication_modules|UDP module]] and through [[ICE-E2D-r5|E2D module]].
* Testing against actual SDDS hardware at Aerospace on Sept 29 and Oct 3.
* Supported in ICE316 on PIC4T and MBT4 cards.

== Packet Pitfalls ==
* No more dual-channel master/slave on same sample, must use timecode for alignment in downstream processing.
* SDDS timecode precision to 250psec, but may not represent 1ms hack below 60kHz sample rate. (2^16 * 250psec).
* Software needs to be enhanced to handle packets robustly.

[[Category:Presentations]]

@@ Line 27: / Line 27: @@
 == SDDS Packets ==
-* Header is fixed 56 bytes with no key.  Data is 1024 bytes.  See [https://downloads.ice-online.biz/datasheets/SDDSPacket.doc SDDSPacket.doc]
+* Header is fixed 56 bytes with no key.  Data is 1024 bytes.  See [https://downloads.ice-online.com/datasheets/SDDSPacket.doc SDDSPacket.doc]
 * Midas file is type 1000, format=SB|SI with PACKET=SDDS keyword in main header.
 * Theoretical max data throughput is 111Mby/sec.  Raw 125Mby/sec less overhead (gap=1%, ether=5.5%, sdds=5.5%)

Packet-Based Architecture - Revision history

Wikiadmin: Text replacement - "ice-online.biz" to "ice-online.com"

Wikiadmin at 16:54, 12 October 2018

Wikiadmin: Created page with "== Packet-based Hardware == * Seven of the 20+ I/O Modules in production are packet-based. * These include FPDP, FPQC, GXD, UDP, SONET, and SONET2. * Systems in the field cur..."