Fundamental Technologies

Voyager LECP Pages

DESCRIPTION OF MASTER RATE TAPE HEADER VARIABLES

(See also MRT Record Header for CR5A.)

INDEX

ITEM

VARIABLE

 TYPE

DESCRIPTION
1

1

SCID

 I*1

Spacecraft Identification - identifies the spacecraft transmitting this data
1=Voyager 1
0=Voyager 2

 

2

MODE

 I*1

Contains the space telemetry mode
0116=CR2
0216=CR3
0316=CR4
0416=CR5
0516=CR6
0716=CR1
0A16=FE
0816=NE
1816=CR5A
2916=CR5A
Spacecraft Event Time - contains the Greenwich Mean of the first bit of the first spacecraft minor frame used in this LECP major frame.

2

3

SCETH

I*2

Spacecraft Event Time, Hour - number of hours since the beginning of the current year plus 24. For the one hour interval Jan 1, 0000-0059 UT, SCET=24. The Day of Year may be computed using DAY=(SCETH/24).

3

4

SCETS

I*2

Spacecraft Event Time, Sec - is the number of seconds since the beginning of the current hour.

4

5

SCETMS

I*2

Spacecraft Event Time, Milliseconds - is the number of milliseconds since the beginning of the current second.

5

6

SCETY

I*2

Spacecraft Event Time, Year - contains the last two digits of the current year (i.e., 77, 78)

6

7

G18ID

I*1

Group 18 Identification - contains the number of the LECP data group being readout at the end of the current LECP major frame.
 

8

SCETF

I*1

Spacecraft Event Time Flag - indicates that the spacecraft clock has been corrected in some manner in the J.P.L. processing. Bit 0 indicates correction to the line count (0=none, 1=corrected), bit 1 the MOD60 counter and bit 2 the MOD216counter.
7

9

MOD216

 I*2

Mod216 Spacecraft Clock Word - contains the spacecraft Mod216 word for the first minor frame of the current record. This word is incremented every 48 minutes on the overflow of the Mod60 counter.

8

10

M60

 I*2

Mod60 Spacecraft Clock Word - contains the spacecraft Mod60 word for the first minor frame of the current record. It has a range of 0 to 59 and is incremented every 48 seconds at the overflow of the line counter.

9

11

LC

 I*2

Spacecraft Line Counter - contains the line count for the first minor frame in the current record. LC ranges from 1 to 80010 and is incremented every 0.06 seconds.

10

12

S1

I*2 LECP Status Word 1 , 10 bits, right justified
11

13

S2

I*2 LECP Status Word 2 , 10 bits, right justified
12

14

S3

I*2 LECP Status Word 3 , 10 bits, right justified
13

15

S4

I*2 LECP Status Word 4 , 10 bits, right justified
14

16

S5

I*2 LECP Status Word 5 , 10 bits, right justified
15

17

S6

I*2 LECP Status Word 6 , 10 bits, right justified
16

18

MP

I*2

LECP Motor Position - contains the motor position at the end of the current record. Bit 0 is set if the status word indicates motor centering, it is zero otherwise. Bits 1-3 contain the motor position with 0-7 corresponding to sector 1 thru 8 respectively. MP=1 if motor position is unknown.

17

19

NMS

I*2

Number of Motor Steps - indicates the number of motor steps within the current LECP Major Frame. Turn arounds in Sectors 8 and 1 or 2 are considered to be two steps.

18

20

LATEMP

I*2

LECP Log. Amp. Temperature - contains the log. amp. temp. (oC x 128. LATEMP= -9999 if the temperature is unknown.

19

21

TTEMP

I*2

LECP Telescope Temperature - contains the telescope temperature (oC) x 128. TTEMP= -9999 if the temperature is unknown.

20

22

BAI

I*2

Basic Accumulation Interval - contains the number of milliseconds of accumulation times for the group 1 and 2 logics.

21

23

NG

I*2

Number of Groups - indicates the number of rate groups included in the current major frame.

22

24

MRT/MPT

I*2

Master Rate Tape/Master Pulse Tape - indicates whether this record is a master rate or master pulse record.
01 = Master Rate Record, 02 = Master Pulse Record

23

25

VN

I*2

Version Number - indicates the version of S1P used to process the current data.

24

26

LEPT/LEMPA

 I*2 Indicates data type in record.
-1=Don't know
0=LEPT
1=LEMPA
"Normal"
NE Logics in G3, 5, 6, 7, 9, 15
25  

RED.A/B

 I*2 Redundancy A or B logic flag.
26  

Proc. Stat.

 I*2 Check SW4 for 50/50. If 50/50 then Item 26.
0=LEPT Norm F. E.
1=LEMPA
Also check DQW 14-15=11
27  

Stepping
Rate Sec.

 I*2 Motor stepping rate

*originally Table B2

Next: LECP Status Words

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Last modified 5/4/05, Tizby Hunt-Ward
tizby@ftecs.com
Original page by I. Robertson