Products 35 & 36: Cis events
DESC: CIS Products: monitor rates P35 and selected events P36.
HIST: 96-02-05 DWC Created file (based on P-MASS.ASM)
96-02-07 DWC/CAI Debug P35. v2.05
96-02-08 DWC/CAI Fix seq count mask (now C3FF was C0FF). v2.05
96-03-26 DWC Add P36. v2.06
96-04-01 CAI Debug P36. v2.06
96-04-11 CAI Redefine P35 product as one 256-word pkt;
add sweep number as first (257th) word; fix
pointer errors; add sweep_collect update for
P36 alone; adj sweep/e-step logic. v2.06
96-04-24 CAI Change sweep_b_i to SRP-relative. v2.07
96-04-30 CAI Fix errors in P36 event select; ignore events
during retrace. v2.08
96-05-02 CAI Revise GET_CIS logic. v2.08
96-05-07 CAI Fill P36 tlm pkt from as many sweeps as
necessary (major rev of GET_CIS). v2.08
07-06-96 AMD Ported the code to ESIC. Replaced everywhere P27 by
P35 and P28 by P36. Reduced the expected sweeps to 16.
03-14-97 AMD V2.23 Removed last step contribute according to
CIS-1 v2.15
NOTE: PRODUCT 35 GENERATION
Product 35 (Monitor Rates) collects 16 rate counters for the
selected half (LS or HS) of the analyzer. Only the first 16
of 24 counters are read. The counters are read out each
e-step (32 times per sweep), but are averaged into 16 energy
bins for each counter. After 2 spins, a telemetry packet containing
2 blocks is generated. Counters in the telemetry packet are log-compressed
to 8 bits, giving a product size of 256 data words plus one sweep number word
(0, 1..15).
Product 35 uses a single summation buffer of 512 16-bit words
At the end of 32 spins, collection suspends until the end
of the product interval, and then restarts. Because this
product uses single buffering, the minimum achievable
product interval is about 18 spins.
P35 SUMMATION BUFFER
Buffer Sweep E-bin Counter
Offset No. No. No.
------ ----- ------ -------
0 0,1 0 0
1 0,1 0 1
2 0,1 0 2
... ... ... ..
15 0,1 0 15
16 0,1 1 0
17 0,1 1 1
... ... ... ..
255 0,1 15 15
256 2,3 0 0
... ... ... ..
511 2,3 15 15
P35 TELEMETRY PACKET FORMAT
The packet buffer contains compressed, summed rate counters
from four sweeps (four spins). The first half of the buffer
holds 16 energies by 16 rate counters for the first sweep
(spin), and the second half similarly reports the second
sweep (spin). A 257th word is added at the beginning of
the packet just after the packet header; this word is the
number of the first of the four sweeps contained in the packet.
Since each product covers two sweeps, eight products are
needed to cover all 16 sweeps.
Rel. Word Sweep
Packet Sweep Energy Counter 0 Numbers
Offset No. No. No. (hex) (dec)
------ ----- ------ ------- ----- --------
0 (sweep number 0,4,8,...,28) 0000 0-3
1 0,1 0 0:1 (MSH:LSH) 0004 4-7
2 0,1 0 2:3 0008 8-11
3 0,1 0 4:5 000C 12-15
... ... ... ... 0010 16-19
8 0,1 0 14:15 0014 20-23
9 0,1 1 0:1 0018 24-27
10 0,1 1 2:3 001C 28-31
... ... ... ...
128 0,1 15 14:15
129 2,3 0 0:1
... ... ... ...
256 2,3 15 14:15
CODIF Rate Counters Reference:
No. Name Description
------ ------ ---------------------------------
0 PF1 Start Position 1
1 PF2 Start Position 2
2 PF3 Start Position 3
3 PF4 Start Position 4
4 PF5 Start Position 5
5 PF6 Start Position 6
6 PF7 Start Position 7
7 PF8 Start Position 8
8 PR1 Stop Position 1
9 PR2 Stop Position 2
10 CSEV Single Valid Event Flag
11 VALID Valid Event Flag
12 VALN Not Valid Event Flag
13 CPOLL Event Poll Flag (total starts)
14 CNT Single Events Missed by Immed I/O
15 SF TAC Start Flag
P35 MEMORY USE
The summation buffer memory is reused for the telemetry
packet buffer. In addition four words are allocated just
before the summation buffer for a 2-word packet handling
structure and 2-word packet header. Memory use is:
Length
(words) Description
------ ---------------
2 packet handling structure
2 packet header
512 summation buffer
------
516 total per product buffer
6 product variables
------
522 1-buffer allocation
27 task tss (at prod task creation)
------
549 total allocation for P35
PRODUCT 36 GENERATION
Product 36, Selected Events, collects TOF during specified
sweeps, synchronous with Monitor Rate collection (if P35
is active). P36 monitors the TOF event interface via DMA data
collection. Up to 512 events are stored in the event buffer.
After each spin, a telemetry packet containing events from
one sweep is generated. If the events from one sweep do
not fill the packet, events from succeeding sweeps are
processed until the packet is full. At the end of 16 spins,
collection suspends until the end of the product interval,
and then restarts.
P36 MEMORY USE
The event buffer memory is not reused for the telemetry
packet buffer. Instead, a separate packet buffer is used.
Four words are allocated just before the packet buffer for
a 2-word packet handling structure and 2-word packet header.
Memory use is:
Length
(words) Description
------ ---------------
2 tlm packet handling structure
2 tlm packet header
72 tlm packet buffer
512 event buffer
------
588 total per product buffer
6 product variables
------
594 allocation
27 task tss (at prod task creation)
------
621 total RAM allocation for P36
P36 DATA COLLECTION
The events are collected from the DPU Event board via a
DMA interface. The DMA interface is configured to prevent
periods of extremely high event frequency from excessively
preempting the CPU by monopolizing the bus. The event
buffer size is 512 words, the max # of events per
22.5 degree period.
The 16-bit TOF event data in the DMA event buffer is:
DMA TOF EVENT BIT DEFINITIONS
*-------*---*---*---*-----------*-------------------------------*
| 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 |
*-------|---|---|---|-----------|-------------------------------*
| 0 0 ps sen ep es tof |
*-------*---*---*---*-----------*-------------------------------*
MSbits: 00z = TOF event data; 11z = HV sector marker
ps = proton suppression (0 = all, 1 = 1/16)
sen = selected sensitivity (0 = L, 1 = H) (ignored by P35/P36)
ep = event stop address - (ignored by P35/P36)
es = event start address (anode #, 0-7)
tof = time of flight (00-FFh)
If the two MSbits equal 00z, the word is a TOF event
(defined above).
If the two MSbits equal 11z, the word is a HV sector marker
(defined below).
DMA HV MARKER BIT DEFINITIONS
*---------------*-----------------------------------------------*
| 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 |
*---------------|-----------------------------------------------*
| 1 1 1 1 sector |
*---------------*-----------------------------------------------*
sector = HV step number since SRP+phase (0000-7FFh,0- 2047),
encompassing 4 HV steps per e-step, 32 e-steps per sweep,
and 16 sweeps per spin as follows:
*---------------*-----------------------------------------------*
| 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 |
*---------------|-------------------|-------------------|-------*
| 1 1 1 1 0 sweep (0-15) e-step (0-31) HVstep |
*---------------*-------------------*-------------------*-------*
P36 TELEMETRY PACKET FORMAT
The 24-bit events are formatted for the packet buffer as
follows:
MSb
*---------------*---------*------------------------*
| 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 |...
*---------------|---------|------------------------*
| sweep es tof |...
*---------------*---------*------------------------*
LSb
*----*----------------------------*
...| 16 17 18 19 20 21 22 23 |
*----|----------------------------*
...| ps energy |
*----*----------------------------*
sweep = sweep number, 0-31
es = event start address (anode #, 0-7)
tof = time of flight
ps = proton suppression (0 = all, 1 = 1/16)
energy = energy step number, 0-123 (of 0-127)
A 72-word telemetry packet contains 48 events. Two 24-bit
events are packed into three 16-bit packet words as follows:
Pkt Word 0, bits 0-15: Event 0, bits 0-15 (MSbits)
Pkt Word 1, bits 0-7 (MSH): Event 0, bits 16-23 (LSbits)
Pkt Word 1, bits 8-15 (LSH): Event 1, bits 0-7 (MSbits)
Pkt Word 2, bits 0-15: Event 1, bits 8-23 (LSbits)
P35 AND P36 DATA COLLECTION
The SECTOR_ISR routine calls GET_CIS every sector interrupt
to collect data from the TOF counters (for P35) and Event
register (for P36). Data is collected during only one sweep
each spin. The selected sweep is rotated by one each spin,
covering all 16 sweeps in 32 spins.
If both P35 and P36 are active, GET_CIS synchronizes data
collection as follows: wait for P35 ready and P36 ready
and correct sweep; then collect for one sweep. If the
P36 tlm pkt is not full, continue P36 collection until
full.
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