Fundamental Technologies

Galileo Spacecraft Pages

4. EPD Telemetry Packet Definitions

Source: R. C. Moore, SDO/PAO 0040, Jan. 1981

Byte Chan
  No.
Bits   per
Chan
Bit
Check-sum
Channel
Identification
Conversion Rule Comments
1 1 8 8 Subcommutated  housekeeping and status (A function of subcom cursor. Value of cursor =7*(Mod13)+(Mod7)+1)
C=7*ch. 23+ch 22+1
Subcommutated housekeeping and status data are defined by R. C. Moore, memo of 8/26/79.
2 2 1 9Scan error0=no error
1=error detected by motor controller
Scan error means motor did not reach desired sector position.
  31 10 Fast scan abort flag 0=normal
1=fast scan
was recently aborted
Automatic fast scan abort occurs when motor's capacitor depth of discharge is too large.
  41 11 Emergency count flag 0=normal
1="emergency count number," modulo 32, occupies channels 5, 6, and 7 instead of direction indicator, and motor position code. Motor controller is in its "emergency" mode.
Emergency count number, when present, equals 16B4+8B5+4B6+2B7+B8
  51 12 Direction indicator 1=clockwise
0=counterclockwise
Stepping platform motor is bi-directional.
  61 13 Centerline indicator 0=not on centerline
1=on centerline
Off centerline means motor is not accurately aligned with desired sector.
  73 16 Motor position code 4B6+2B7+B8=P Position code for 8 sectors as follows:
P=0=sector 0 (shield)
P=1=sector 1
P=2=sector 2
P=3=sector 3
P=4=sector 4
P=5=sector 5
P=6=sector 6
P=7=sector 7
3 8 8 24Memory dump, alias "memory trickle readout"   Contents of ROM or RAM as addressed by memory dump cursor. 65,536 bytes are dumped into telemetry every 12 hr, 8 min, 10 2/3 sec.
4 9 8 32Memory dump cursor (8 LSBs)  8 MSBs of memory dump cursor are in subcommed housekeeping/status
5 10 8 40Number of commands executed, modulo 256 N=128B1+64B2+32B3
+16B4+8B5+4B6
+2B7+B8
At power-on, N=0. Increments by one with each command executed.
6 11 8 48Packet parity  Exclusive OR of all other bytes in this packet (bytes 15,7-76).
7 12 8 56 Operation code of last command executed See command listings in GLL-3-290. Comparison with byte 5 reveals missed commands.
8 13 1 57(spare)    
  141 58 Power monitor flag 0=normal
1=power to EPD has recently been interrupted
Automatic EPD reset and resync following power interruption.
  151 59 Bus adapted parity error flag 0=normal (good parity)
1=EPD bus adapter recently detected bad parity on supervisory data line.
Bad parity could mean an error in real-time clock transfer or in EPD bus command.
  161 60 Resynchronization flag 0=normal
1=EPD recently resynced to CDS
Resync occurs at power-on, following a power interruption, or at execution of "EPD resync to CDS" bus command.
  171 61 Cease scan flag 0=normal
1=motor controller has entered "cease scan" mode
 
  181 62 Motor in motion flag 0=normal
1=motor was in motion when data contained in this logical record were gathered.
Data taken while motor is in motion are not to be correlated with data taken while motor is "on sector."
  191 63 Singles/background flag 0=s/b format L
1=s/b format J or s/b format J' (contents of channel 20 determine whether J or J' is used.)
s/b formats are described in S3D-79-088* and S3D-79-090* (*not available on this website; reference APL S3 Division archives).
  201 64 J/J' indicator 0=CMS mode J
1=CMS mode J'
Mode J is used when CMS 180 deg. end is in use. Mode J' is used when CMS 0 deg. end is in use.
9 21 1 65Mod 2 counter, alias "odd packet indicator" Always logic 0. (Bytes 1 through 76 are in the "even" packet.) Used to determine if packet is first half or second half of logical record. (Compare with channel 107.)
  223 68 Mod 7 counter N=4B2+2B3+B4
0<=N<=6
N increments by one every packet. One EPD packet per LRS minor frame. 91 LRS minor frames per major frame. (See channel 108.)
  234 72 Mod 13 counter M=8B5+4B6+2B7+B8
0<=M<=12
M increments by one every 7 packets.
10 24 8 80CMS PHA dEJ no. 1 dEJ1=128B1+64B2+32B3+
16B4+8B5+4B6+2B7+B8
On each Mod 7=0 (inc. 1/packet)
11 25 8 88CMS PHA dEK no. 1 dEK1=128B1+64B2+32B3+ 16B4+8B5+4B6+2B7+B8 CMS PHA is replaced by channels 1-12 of LEMMS PHA.
12 26 8 96CMS PHA TOF no. 1 TOF1=128B1+64B2+32B3+1
6B4+8B5+4B6+2B7+B8
The remaining 35 channels come in 7 groups of 5 in LEMMS PHA in this and the following 6 packets.
13 27 2 98J ID no. 1J1 ID=2B1+B2 J ID=0=Jc
J ID=1=Jb
J ID=3=Ja
  282 100 Last transmited Priority no. 1 P1=2B3+B4 P=0=priority I
P=1=priority II
P=2=priority III
P=3=priority IV
  29 4 104 CMS PHA rate channel code no. 1 R1=8B5+4B6+2B7+B8 Bits B5 and B6 determine event's priority.
R ValueRate Channel
0CM5
1CN0
2CN1
3CH5
4CH2
5CH3
6CH4
7(not used)
8CM2
9CM3
10CM4
11(not used)
12CA2
13CA3
14CA4
15(not used)
Rate
Channel
Priority
CM5

I

CN0
CN1
CH5
CH2

II

CH3
CH4
CM2

III

CM3
CM4
CA2

IV

CA4
CA4
 14 308 112 CMS PHA dEJ no. 2 (same as dEJ1)  
15 318 120 CMS PHA dEK no. 2 (same as dEK1)  
16 328 128 CMS PHA TOF no. 2 (same as TOF1)  
17 332 130 J ID no. 2 (same as J1 ID) (See comments for channel 27.)
  342 132 Last transmitted priority no. 2 (same as P1) (See comments for channel 28.)
  354 136 CMS PHA rate channel code no. 2 (same as R1) (See comments for channel 29.)
18 368 144 CMS PHA dEJ no. 3 (same as dEJ1  
19 378 152 CMS PHA dEK no. 3 (same as dEK1)  
20 388 160 CMS PHA TOF no. 3 (same as TOF1)  
21 392 162 J ID no. 3 (same as J1 ID) (See comments for channel 27.)
  402 164 Last transmitted Priority No. 3 (same as P1) (See comments for channel 28.)
  414 168 CMS PHA rate channel code no. 3 (same as R1) (See comments for channel 29.)
22 428 176 LEMMS PHA spectrum element no. 1 Mantissa=8B5+4B6+2B7+B8
Exponent=8B1+4B2+2B3+B4
If exponent=15, then value=mantissa.
Else value=(mantissa+16).2exponent.
See bytes 10-21.
23 438 184 LEMMS PHA spectrum element no. 2 (same as for channel 42)  
24 448 192 LEMMS PHA spectrum element no. 3 (same as for channel 42)  
25 458 200 LEMMS PHA spectrum element no. 4 (same as for channel 42)  
26 468 208 LEMMS PHA spectrum element no. 5 (same as for channel 42)  
27,28 4710 218 E0 no. 1 Exp=16B1+8B2+4B3+2B4+B5
Man=16B6+8B7+4B8+2B1+B2
If exp=31, then value=mantissa.
Else value=(man+32) .2 exp
LEMMS electrons
.015 MeV to .030 MeV
28,29 4810 228 E1 no. 1 Exp=16B3+8B4+4B5+2B6+B7
Man=16B8+8B1+4B2+2B3+B4
If exp=31, then value=man.
Else value=(man+32) .2 exp
LEMMS electrons
.030 MeV to .045 MeV
29,30 4910 238 A0 no. 1 Exp=16B5+8B6+4B7+2B8+B1
Man=16B2+8B3+4B4+2B5+B6
If exp=31, then value=man.
Else value=(man+32) .2 exp
LEMMS z>=1
.020 MeV to .030 MeV
30,31 5010 248 A1 no. 1 Exp=16B7+8B8+4B1+2B2+B3
Man=16B4+8B5+4B6+2B7+B8
If exp=31, then value=man.
Else value=(man+32) .2 exp
LEMMS z>=1
.030 MeV to .050 MeV
32,33 5110 258 A2 no. 1 (same as ch. 47) LEMMS z>=1
.050 MeV to .100 MeV
33,34 5210 268 E2 no. 1 (same as ch. 48) LEMMS electrons
.045 MeV to .060 MeV
34,35 5310 278 E3 no. 1 (same as ch. 49) LEMMS electrons
.060 MeV to .100 MeV
35,36 5410 288 F0 No. 1 (same as ch. 50) LEMMS electrons
.100 MeV to .200 MeV
37,38 5510 298 F1 no. 1 (same as ch. 47) LEMMS electrons
.200 MeV to .350 MeV
38,39 5610 308 A3 no. 1 (same as ch. 48) LEMMS z>=1
.100 MeV to .250 MeV
39,40 5710 318 A4 no. 1 (same as ch. 49) LEMMS z>=1
.250 MeV to .500 MeV
40,41 5810 328 A5 no. 1 (same as ch. 50) LEMMS z>=1
.500 MeV to .800 MeV
42,43 5910 338 A6 no. 1 (same as ch. 47) LEMMS z>=1
.800 MeV to 1.60 MeV
43,44 6010 348 A7 no. 1 (same as ch. 48) LEMMS z>=1
1.60 MeV to 3.40 MeV
44,45 6110 358 F2 no. 1 (same as ch. 49) LEMMS electrons
.350 MeV to .600 MeV
45,46 6210 368 F3 no. 1 (same as ch. 50) LEMMS electrons
.600 MeV to 1.00 MeV
47,48 6310 378 CE2 (same as ch. 47) CMS electrons
100 keV to 200 keV
48,49 6410 388 CE3 (same as ch. 48) CMS electrons
200 keV to >300 keV
49,50 6510 398 CE1 (same as ch. 49) CMS electrons
50.0 keV to 100 keV
50,51 6610 408 CP1 (same as ch. 50) CMS protons
200 keV to 290 keV
52,53 6710 418 E0 no. 2 (same as ch. 47) LEMMS electrons
.015 MeV to .030 MeV
53,54 6810 428 E1 no. 2 (same as ch. 48) LEMMS electrons
.030 MeV to .045 MeV
54,55 6910 438 A0 no. 2 (same as ch. 49) LEMMS z>=1
.020 MeV to .030 MeV
55,56 7010 448 A1 no. 2 (same as ch. 50) LEMMS z>=1
.030 MeV to .050 MeV
57,58 7110 458 CP2 (same as ch. 47) CMS protons
290 keV to 500 MeV
58,59 7210 468 CP3 (same as ch. 48) CMS protons
500 keV to 1.40 MeV
59,60 7310 478 CH0 (same as ch. 49) CMS heavy nuclei
.025 MeV to .035 MeV
60,61 7410 488 CH1 (same as ch. 50) CMS heavy nuclei
.070 MeV to .100 MeV
62,63 7510 498 A8 (same as ch. 47) LEMMS z>=2
3.40 MeV to 12.4 MeV
63,64 7610 508 DC0 (same as ch. 48) LEMMS z>=1
15.5 MeV to 28 MeV
64,65 7710 518 DC1 (same as ch. 49) LEMMS z>=1
42 MeV to 55 MeV
65,66 7810 528 DC2 (same as ch. 50) LEMMS electrons
>=2 MeV
67,68 7910 538 DC3 (same as ch. 47) LEMMS electrons
>=11 MeV
68,69 8010 548 B0 (same as ch. 48) LEMMS z=1
3.4 MeV to 10.5 MeV
69,70 8110 558 B1 (same as ch. 49) LEMMS electrons
1.5 MeV to 10.5 MeV
70,71 8210 568 B2 (same as ch. 50) LEMMS z=2
12.4 MeV to 250 MeV
72,73 8310 578 CA1 (same as ch. 47) CMS alphas
.17 MeV to .39 MeV
73,74 8410 588 CA3 (same as ch. 48) CMS alphas
.38 MeV to .80 MeV
74,75 8510 598 CA4 (same as ch. 49) CMS alphas
.80 MeV to 1.8 MeV
75,76 8610 608 CM1 (same as ch. 50) CMS medium nuclei
.16 MeV to .45 MeV
77 878 616 Subcommutated housekeeping and status (A function of subcom cursor. Value of cursor=13x(mod 7)+(mod 13)+1)
C=13 x channel 108 + channel 109+1
(same as for ch. 1)
78 881 617 Scan error (same as ch. 2) (same as for ch. 2)
  891 618 Fast scan abort flag (same as ch. 3) (same as for ch. 3)
  901 619 Emergency count flag 0=normal.
1="emergency count number," modulo 32, occupies channels 91, 92, and 93 instead of direction indicator, centerline indicator, and motor position code. Motor controller is in its "emergency" mode
.
(same as for ch. 4)
  911 620 Direction indicator (same as ch. 5) (same as for ch. 5)
  921 621 Centerline indicator (same as ch. 6) (same as for ch. 6)
  933 624 Motor position code (same as ch. 7) (same as for ch. 7)
79 948 632 Memory dump, alias "memory trickle readout"   (same as for ch. 8)
80 958 640 Memory dump cursor (8 LSBs)   (same as for ch.  9)
81 968 648 Number of commands executed, modulo 256 (same as ch. 10) (same as for ch. 10)
82 978 656 Packet parity   (same as for ch. 11)
83 988 664 Operation code of last command executed (same as ch. 12) (same as for ch. 12)
84 991 665 (spare)    
  1001 666 Power monitor flag (same as ch. 14) (same as for ch. 14)
  1011 667 Bus adapter parity error flag (same as ch. 15) (same as for ch. 15)
  1021 668 Resynchronization flag (same as ch. 16) (same as for ch. 16)
  1031 669 Cease scan flag (same as ch. 17)  
  1041 670 Motor in motion flag (same as ch. 18) (same as for ch. 18)
  1051 671 Singles/background flag 0=s/b format L
1=s/b format J or s/b format J' (Contents of channel 106 determine whether J or J' is used.)
(same as for ch. 19)
  1061 672 J/J' indicator (same as ch. 20) (same as for ch. 20)
85 1071 673 Mod 2 counter, alias "odd packet indicator" Always logic "1." (Bytes 77 through 152 are in the "odd" packet.) Compare with ch. 21.
  1083 676 Mod 7 counter (same as ch. 22) (same as for ch. 22)
  1094 680 Mod 13 counter (same as ch. 23) (same as for ch. 23)
86 1108 688 CMS PHA dEJ no. 4 (same as ch. 24)  
87 1118 696 CMS PHA dEK no. 4 (same as ch. 25)  
88 1128 704 CMS PHA TOF no. 4 (same as ch. 26)  
89 1132 706 J ID no. 4 (same as ch. 27) (same as for ch. 27)
  1142 708 Last transmitted priority no. 4 (same as ch. 28) (same as for ch. 28)
  1154 712 CMS PHA rate channel code no. 4 (same as ch. 29) (same as for ch. 29)
90 1168 720 CMS PHA dEJ no. 5 (same as dEJ1)  
91 1178 728 CMS PHA dEK no. 5 (same as dEK1)  
92 1188 736 CMS PHA TOF no. 5 (same as TOF1)  
93 1192 738 J ID no. 5 (same as J1 ID) (same as for ch. 27)
  1202 740 Last transmitted priority no. 5 (same as P1) (same as for ch. 28)
  1214 744 CMS PHA rate channel Code no. 5 (same as R1) (same as for ch. 29)
94 1228 752 CMS PHA dEJ no. 6 (same as dEJ1)  
95 1238 760 CMS PHA dEK no. 6 (same as dEK1)  
96 1248 768 CMS PHA TOF no. 6 (same as TOF1)  
97 1252 770 J ID no. 6 (same as J1 ID) (See comments for channel 27.)
  1262 772 Last transmitted priority no. 6 (same as P1) (same as for ch. 28)
  1274 776 CMS PHA rate channel code no. 6 (same as R1) (same as for ch. 29)
98 1288 784 LEMMS PHA spectrum element no. 6 (same as ch. 42) Energy bin number=5x (channel 109)+1
99 1298 792 LEMMS PHA spectrum element no. 7 (same as ch. 42) Energy bin number=5x (channel 109)+2
100 1308 800 LEMMS PHA spectrum element no. 8 (same as ch. 42) Energy bin number=5x (channel 109)+3
101 1318 808 LEMMS PHA spectrum element no. 9 (same as ch. 42) Energy bin number=5x (channel 109)+4
102 1328 816 LEMMS PHA spectrum element no. 10 (same as ch. 42) Energy bin number=5x (channel 109)+5
103,104 13310 826 E0 no. 3 (same as ch. 47) LEMMS electrons .015 MeV to .030 MeV
104,105 13410 836 E1 no.3 (same as ch. 48) LEMMS electrons .030 MeV to .045 MeV
105,106 13510 846 A0 no. 3 (same as ch. 49) LEMMS z>=1
.020 MeV to .030 MeV
106,107 13610 856 A1 no. 3 (same as ch. 50) LEMMS z>=1
.030 MeV to .050 MeV
108,109 13710 866 A2 no. 2 (same as ch. 47) LEMMS z>=1
.050 MeV to .100 MeV
109,110 13810 876 E2 no. 2 (same as ch. 48) LEMMS electrons .045 MeV to .060 MeV
110,111 13910 886 E3 no. 2 (same as ch. 49) LEMMS electrons .060 MeV to .100 MeV
111,112 14010 896 F0 no. 2 (same as ch. 50) LEMMS electrons .100 MeV to .200 MeV
113,114 14110 906 F1 no. 2 (same as ch. 47) LEMMS electrons .200 MeV to .350 MeV
114,115 14210 916 A3 no. 2 (same as ch. 48) LEMMS z>=1
.100 MeV to .250 MeV
115,116 14310 926 A4 no. 2 (same as ch. 49) LEMMS z>=1
.250 MeV to .500 MeV
116,117 14410 936 A5 no. 2 (same as ch. 50) LEMMS z>=1
.500 MeV to .800 MeV
118,119 14510 946 A6 no. 2 (same as ch. 47) LEMMS z>=1
.800 MeV to 1.60 MeV
119,120 14610 956 A7 no. 2 (same as ch. 48) LEMMS z>=1
1.60 MeV to 3.40 MeV
120,121 14710 966 F2 no. 2 (same as ch. 49) LEMMS electrons
.350 MeV to .600 MeV
121,122 14810 976 F3 no. 2 (same as ch. 50) LEMMS electrons
.600 MeV to 1.00 MeV
123,124 14910 986 CM3 (same as ch. 47) CMS medium nuclei
.410 MeV to 1.00 MeV
124,125 15010 996 CM4 (same as ch. 48) CMS medium nuclei
1.00 MeV to 2.70 MeV
125,126 15110 1006 CM5 (same as ch. 49) CMS medium nuclei
2.70 MeV to 10.7 MeV
126,127 15210 1016 CN1 (same as ch. 50) CMS intermediate nuclei
2.00 MeV to 11.7 MeV
128,129 15310 1026 E0 no. 4 (same as ch. 47) LEMMS electrons
.015 MeV to .030 MeV
129,130 15410 1036 E1 no. 4 (same as ch. 48) LEMMS electrons
.030 MeV to .045 MeV
130,131 15510 1046 A0 no. 4 (same as ch. 49) LEMMS z>=1
.020 MeV to .030 MeV
131,132 15610 1056 A1 no. 4 (same as ch. 50) LEMMS z>=1
.030 MeV to .050 MeV
133,134 15710 1066 CH2 (same as ch. 47) CMS heavy nuclei
.110 MeV to .370 MeV
134,135 15810 1076 CH3 (same as ch. 48) CMS heavy nuclei
.33 MeV to .80 MeV
135,136 15910 1086 CH4 (same as ch. 49) CMS heavy nuclei
.80 MeV to 1.7 MeV
136,137 16010 1096 CH5 (same as ch. 50) CMS heavy nuclei
1.7 MeV TO 13 MeV
138,139 16110 1106 SB4 (same as ch. 47)
CHAN
105  
CHAN
106  
RATE
CHAN
00 EB1
01 EB1
10 KS
11 K'S
139,140 16210 1116 SB5 (same as ch. 48)
CHAN
105  
CHAN
106  
RATE
CHAN
00 EB2
01 EB2
10 JbS
11 EB2
140,141 16310 1126 SB6 (same as ch. 49)
CHAN
105  
CHAN
106  
RATE
CHAN
00 FB2
01 FB2
10 FB1
11 FB1
141,142 16410 1136 SB0 (same as ch. 50)
CHAN
105  
CHAN
106  
RATE
CHAN
00 AS
01 AS
10 AS
11 AS
143,144 16510 1146 CA0 (same as ch. 47) CMS alphas
.08 MeV to .19 MeV
144,145 16610 1156 CA2 (same as ch. 48) CMS alphas
.19 MeV to .45 MeV
145,146 16710 1166 SB1 (same as ch. 49)
CHAN
105  
CHAN
106  
RATE
CHAN
00 BS
01 BS
10 LS
11 BS
146,147 16810 1176 SB2 (same as ch. 50)
CHAN
105  
CHAN
106  
RATE
CHAN
00 CS
01 CS
10 JaS
11 Ja'S
148,149 16910 1186 CM0 (same as ch. 47) CMS medium nuclei
.08 MeV to .15 MeV
149,150 17010 1196 CM2 (same as ch. 48) CMS medium nuclei
.14 MeV to .59 MeV
150,151 17110 2306 CN0 (same as ch. 49) CMS intermediate nuclei
.91 MeV to 2.0 MeV
151,152 17210 1216 SB3 (same as ch. 50)
CHAN
105  
CHAN
106  
RATE
CHAN
00 DS
01 DS
10 JcS
11 Jc'S

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Updated 10/26/04, T. Hunt-Ward
tizby@ftecs.com