Updated SDP timing description and BSN aligner selection to almost final...

Updated SDP timing description and BSN aligner selection to almost final state. Updated other txt files at some points.

applications/lofar2/doc/prestudy/desp_hdl_design_article.txt

-. Distinguish beteen state registers and pipeline registers.
-  The state registers keep the state of the function and the function itself is programmed in combinatorial logic.
+Idea / rule: Distinguish beteen state registers and pipeline registers.
+
+. The state registers keep the state of the function and the function itself is programmed in combinatorial logic.
   In this way the pipelining that is needed to achieve timing closure can be added independent of the function.
   This approach could be described in a paper, because it is quite significant and differs from the well known
   Gailser approach (that uses RL=1 and does not separate state from pipeline). AXI uses RL=0 but need to check 
@@ -28,5 +29,5 @@
 
 
 Ref:
- tools/oneclick/doc/desp_firmware_dag_erko.txt : Secion 6) VHDL design
- tools/oneclick/doc/desp_firmware_overview.txt
+ $RADIOHDL/tools/oneclick/doc/desp_firmware_dag_erko.txt
+ $RADIOHDL/tools/oneclick/doc/desp_firmware_overview.txt
\ No newline at end of file

applications/lofar2/doc/prestudy/station2_sdp_icd.txt

@@ -22,25 +22,32 @@ UDP link control
 - UDP/IPv4
   . UDP checksum (not used in LOFAR1)
   
-
+> nslookup <hostname> # e.g. <astron.nl> to find IP address
+> sudo arp
+> ping <IP address>  # to find MAC address for IP address ?
 
 
 LFAA-CSP_Low : OSI (Open Systems Interconnection) layers
 
-7 Application  : Not applicable, this is the level where the STAT and CEP products each perform their allocated functions.
+7 Application  : Not applicable, this is the level where the STAT and CEP products each perform their
+                 allocated functions.
 6 Presentation :
   - SPEAD header
     header first word:
-      magic = 0x53 ='S' 8b, version = 0x4 8b, itemPointerWidth = 0x2 8b, HeapAddrWidth = 0x0 8b, rsvd=0 16b, number of items = 0x8 16b
+      magic = 0x53 ='S' 8b, version = 0x4 8b, itemPointerWidth = 0x2 8b, HeapAddrWidth = 0x0 8b, rsvd=0 16b,
+      number of items = 0x8 16b
 
     header items:
-      heap_counter     = coarse channel number (1-511) 16b, packet counter 32b # restart at 0 for new observation, 2k samples per packet --> packet counter wraps after few days
+      heap_counter     = coarse channel number (1-511) 16b, packet counter 32b # restart at 0 for new
+                         observation, 2k samples per packet --> packet counter wraps after few days
       pkt_len          = packet payload length 48b
       sync_time        = unix_epoch_time [s] 48b # last time system was syncrhonised by PPS in seconds since 1 Jan 1970
-      timestamp        = timestamp [ns] 48b      # time of center of first sample in packet since sync_time in ADC sample periods of 1.25 ns
+      timestamp        = timestamp [ns] 48b      # time of center of first sample in packet since sync_time in
+                                                   ADC sample periods of 1.25 ns
       center_freq      = frequency [Hz] 48b      # center frequency of coarse channel (1-511) * 781250 in Hz
       csp_channel_info = rsvd 16b, beam_id 16b, freq_id 16b
-      csp_antenna_info = substation_id (1-512) 8b, subarray_id (1-16) 8b, station_id 16b, nof_contributing_antenna (typ. 256) 16b
+      csp_antenna_info = substation_id (1-512) 8b, subarray_id (1-16) 8b, station_id 16b, nof_contributing_antenna
+                         (typ. 256) 16b
       sample_offset    = payload_offset = 0x0
 
     data
@@ -68,7 +75,10 @@ LFAA-CSP_Low : OSI (Open Systems Interconnection) layers
 L1 ICD 11109 : STAT - CEP
  . Beamlet data
  . Transient buffer read out
- . Subband offload (for AARTFAAC)
+ 
+Not included:
+ . SST, BST, XST, because these are for monitoring and calibration, not for science data
+ . Subband offload for AARTFAAC2.0 will have own EICD
 
 STAT-CEP Beamlet data interface:
 
@@ -82,10 +92,14 @@ STAT-CEP Beamlet data interface:
   . 1b critically PFB, oversampled PFB (or p, q for R_os = p/q)
   . 4b beamlet width in number of bits (default 8 for W_beamlet = 8 bit, instead of BM = beamlet mode)
   . 5b UniBoard2 FPGA id (16 FPGAs for LBA, 16 for HBA in International Station, instead of RSP ID)
+  . ==> Also beamlet scale setting
+  . ==> Number of antenna in beam (core, LBA, HBA inner to make HBA international look like HBA remote)
   
 - CONFIGURATION_ID 8b (used in LOFAR1? intended to refer to the parset that defines this observation)
+  ==> observation ID 32b
 
 - STATION_ID 16b (idem as LOFAR1)
+  ==> or 8b because there are only ~50 stations
 
 - One packet per range of Station beamlets out of 488 beamlets
   . Full band : S_sub_bf * W_beamlet * N_complex / W_byte = 488 * 8b * 2 / 8b = 976 octets
@@ -126,6 +140,9 @@ STAT-CEP Beamlet data interface:
   
 
 - TX_PACKET_COUNT 32b
+  ==> Not useful, because then CEP needs to count Rx packets. Better send filler packets to keep the
+      packet rate at the nominal rate, so that any packet loss is due to the Network and already 
+      clear at OSI 2 layer using lower level tools like Wireshark.
   . OSI transport layer 4
   . Per stream
   . Started at Station power up, increments by 1 for every transmitted packet.

applications/lofar2/doc/prestudy/station2_sdp_m_and_c.txt

@@ -2,7 +2,7 @@
 * Station Control software:
 *******************************************************************************
 
-The Station contains hardware and software devices that deliver the funnctionality of the application
+The Station contains hardware and software devices that deliver the functionality of the application
 [4.1.2.1]. The Station Control software consist of Control and M&C. The Control determines the behaviour
 of the devices in time. Via the M&C the Control can control the devices and monitor them. The M&C uses
 a standard software interface for the Control to access the devices. For the Station M&C the M&C will 
@@ -48,8 +48,12 @@ FPGAs in parallel. The synchronous M&C can be for a single PPS instant or for ev
     
 
 - Use fixed internal sync aligned to PPS
-  . The disadvantage of a fixed interval is that it is inflexible and cannot be controlled by the SCU,
-    This could also be considered an advantage, because it is well defined and does not need control.
+  . In LOFAR1 and APERTIF the sync period is used as fixed update interval for periodic monitoring,
+    periodic control (the beamformer weights) and periodic integration intervals (AST, SST, BST and 
+    XST).
+  . The advantage of a fixed update interval is that it is well defined and does not need control.
+    This can also be a disadvantage because a fixed interval is inflexible and cannot be controlled
+    by the SCU. Probably only for the XST this flexibility is nice to have.
   . With a fixed interval the monitored information may only reflect what happened during the previous
     period. Therefore if the monitoring has to be without gaps in time then the SCU needs to monitor
     and aggregate the information at every period. Using a configurable period this aggregation in the 
@@ -167,4 +171,9 @@ Behaviour of the data points:
                                
 
                                  
-
+Conclusion:
+- Identify casue of error preferrably via a single monitoring point
+- With proper monitoring no test time is needed
+- Support writing status fields in a test mpd for SW - FW interface testing 
+- Use 1 s sync interval of PPS to time period M&C events for all. Optionally support a local BSN scheduler
+  for the XST.