ST5000 Mark IID Telemetry

Change Log
Version Date Comments
1.0 05-Apr-2005 Initial Release
1.1 12-Dec-2005 Add NTRK to slot 12
1.2 26-Jan-2007 Add FWHM bytes.
Target peak is from the fit, not just the peak pixel value.
Replace trackbox mode with the computed mean.
Target flux is mean-subtracted.
Add extra track box.
1.3 10-Jul-2007 Add trackbox status codes
1.4 13-Jul-2007 Add LIS file size, time, crc
1.5 31-Aug-2007 Add ACQ state (slot 60)
1.6 02-Oct-2007 Add millisecond timer (slots 62, 63)
1.7 04-Aug-2011 Add cmd & msg counters
1.8 16-Mar-2013 Add disk usage
1.9 29-Jan-2014 Add Graphics support
1.10 02-Sep-2015 Add GiGE Ethernet Camera support
1.11 11-Feb-2016 Add ST5400 Series Controller items

This section describes the telemetry packet that the Mark IId ST5000 sends out on the serial line.

Notes on the packet layout.

261 (5+112+2*72) bytes (this includes the packet protocol bytes) at 10 Hz requires a comm bandwidth of 20880 bits per second.

The data bytes are encapsulated with sync bytes and a data length according to the ST5000 XMSG protocol.

The packet contains 1, 2, and 4-byte unsigned integers and 4-byte floating point values. The values are encoded (serialized) in big-endian order. The encoding is compatible with the XDR standard. We wrote our own XDR-compatible codec in C and Java; here is the C version, in PDF and source code.

How to read the packet layout.

Frame depth: The ST5000 telemetry is modelled as a NASA-style "major frame" with a depth of 8 minor frames and a minor frame length of 256 slots (excluding protocol bytes). Most items have a subcom depth of 1; they repeat each frame. The subcom-8 items are broken out in separate tables.

Frame rate: The ST5000 sends frames during each frame grab, which by default happens at 10 Hz. The 8-frame depth means that the frame repeats in 0.8 seconds. If you change the exposure time, you also change the telemetry frame rate. If you set the exposure time to 15 video frame periods (0.5 s), then the telemetry slows down to 2 Hz.

Here is a brief desciption of each item.

ST5000 Mark IID Telemetry
Byte Item Comment
-5 Sync 1 0x4a
-4 Sync 2 0x57
-3 Sync 3 0x50
-2 Length 1/2 See the XMSG Protocol
-1 Length 2/2
0 Routing Code 8 (ST5000 MkII)
1 Packet Code 17 (MkIId Telemetry)
2 CRC 1/2 CCITT CRC 16 (x^16+x^12+x^5+x^1)
3 CRC 2/2
4 Tracker ID TBD
5 spare --------------------
6 Frame Number 1/2 (frame % 8) gives the index into the major frame
7 Frame Number 2/2
8 CACS State
9 Tracker State
10 LIS State
11 PIT State
12 # Stars Being Tracked lose roll when this drops to 1
13 Software Input Bits
14 Digital Input Bits
15 Digital Output Bits
16 Reference Quaternion Qi 1/4
20 Reference Quaternion Qj 1/4
24 Reference Quaternion Qk 1/4
28 Reference Quaternion Qw 1/4
32 Disturbance Quaternion Qi 1/4
36 Disturbance Quaternion Qj 1/4
40 Disturbance Quaternion Qk 1/4
44 Disturbance Quaternion Qw 1/4
48 Clock 1/4 UTC seconds since 1970
49 Clock 2/4
50 Clock 3/4
51 Clock 4/4
52 Software Status 1/4 Software Status Bits
53 Software Status 2/4
54 Software Status 3/4
55 Software Status 4/4
56 RAM-A or IRAM Status 1/2 RAM Status Bits
57 RAM-A or IRAM Status 2/2
58 RAM-B or GRAM Status 1/2
59 RAM-B or GRAM Status 2/2
60 ACQ State
61 Various 1-byte subcommed items GigE Camera Items
62 Millisecond Timer 1/2
63 Millisecond Timer 2/2
64 CSR 1 Control Status Register 1
65 CSR 2 Control Status Register 2
66 Process counter Proc id = frame%8
67 Various 1-byte subcommed items graphics module items
68 DAC Channel 0 1/2 Digital to Analog Converters
69 DAC Channel 0 2/2
70 DAC Channel 1 1/2
71 DAC Channel 1 2/2
72 DAC Channel 2 1/2
73 DAC Channel 2 2/2
74 DAC Channel 3 1/2
75 DAC Channel 3 2/2
76 Star Magnitude 1/4 V Magnitude (mili-magnitudes)
77 Star Magnitude 2/4
78 Star Magnitude 3/4
79 Star Magnitude 4/4
80 ADC Channel 0 1/2 ADC Channel = (frame%8)
81 ADC Channel 0 2/2
82 ADC Channel 8 1/2 ADC Channel = (frame%8)+8
83 ADC Channel 8 2/2
84 Various 1-byte subcommed items cohu exposure, tracking items
85 Various 1-byte subcommed items system items, plus LIS good star count
86 Various 2-byte subcommed items triangles, image stats
87 continued
88 Various 4-byte subcommed items alignment angles, DAC windows
89 continued
90 continued
91 continued
92 Various 4-byte subcommed items shims, target, guide star angles
93 continued
94 continued
95 continued
96 Acquired X-position 1/4 floating point pixels
100 Acquired Y-position 1/4 floating point pixels
104 Acquired Peak Value counts, 0-255
105 Acquired Bias estimated background (counts)
106 Acquired Flux 1/2 mean subtracted (counts)
107 Acquired Flux 2/2
108 Catalog ID 1/2 from Lost-in-Space solution
109 Catalog ID 2/2
110 Votes 1/2 from LIS solution
111 Votes 2/2
  Next 68 bytes: subcom-8, trackboxes 1-8
112 Current X-position 1/4  
116 Current Y-position 1/4
120 Current Peak Value counts, 0-255
121 Current Bias estimated background (counts)
122 Current Flux 1/2 mean subtracted (counts)
123 Current Flux 2/2
124 Track box row 1 unsigned bytes
131 Track box row 2 unsigned bytes
138 Track box row 3 unsigned bytes
145 Track box row 4 unsigned bytes
152 Track box row 5 unsigned bytes
159 Track box row 6 unsigned bytes
166 Track box row 7 unsigned bytes
173 Trackbox Status enumerated
174 Target Amplitude 1/2 ADUs
175 Target Amplitude 2/2
176 Current FWHM 1/4 floating point pixels
177 Current FWHM 2/4
178 Current FWHM 3/4
179 Current FWHM 4/4
  End of subcom-8 trackboxes 1-8
180 spare --------------------
181 spare --------------------
182 spare --------------------
183 spare --------------------
  Next 68 bytes: subcom-24, trackboxes 9-32
184 Current X-position 1/4  
188 Current Y-position 1/4
192 Current Peak Value counts, 0-255
193 Current Bias estimated background (counts)
194 Current Flux 1/2 mean subtracted (counts)
195 Current Flux 2/2
196 Track box row 1 unsigned bytes
203 Track box row 2 unsigned bytes
210 Track box row 3 unsigned bytes
217 Track box row 4 unsigned bytes
224 Track box row 5 unsigned bytes
231 Track box row 6 unsigned bytes
238 Track box row 7 unsigned bytes
245 Trackbox Status enumerated
246 Target Amplitude 1/2
247 Target Amplitude 2/2
248 Current FWHM 1/4 floating point pixels
249 Current FWHM 2/4
250 Current FWHM 3/4
251 Current FWHM 4/4
  End of subcom-24 trackboxes 9-32
252 Various 4-byte subcommed items
253 continued
254 continued
255 continued

Various 1-byte subcommed items - Slot 61
Minor Frame Item Comment
2 GigE Frame Count # of received frames
0 GigE Binning pixels, usually 2x2
1 GigE Exposure Time milliseconds
3 GigE Gain dB
5 GigE Offset 0-255
6 GigE Gamma 0.5-2.0 (times 100)
4 GigE NIR Mode 0=Off, 1=HQ, 2=Fast
7 GigE Process Counter WID 9

Various 1-byte subcommed items - Slot 67
Minor Frame Item Comment
0 CSR 3 (aka GCR) ST52523/ST5452 Graphics Control Register
1 GBPR ST52523/ST5452 Graphics Bit Plane Register
2 GIR ST52523/ST5452 Graphics Intensity Register
3 GPR ST52523/ST5452 Graphics Page Register
4 ICR ST5452 Image Control Register
5 IPR ST5452 Image Page Register
6 GPOR ST5452 General Purpose Output Register
7 spare  

Various 1-byte subcommed items - Slot 84
Minor Frame Item Comment
0 nframes exposure time, in units of video frames. 3 is 10 Hz.
1 shutter shutter value
2 cgain camera gain (0 = high, 255 = low)
3 track start start here in the list of 32 acquired stars
4 track count track this many stars
5 track target used as boolean; move to guide star, or just hold steady?
6 nacq number of stars acquired
7 ntrk number of stars still being tracked

Various 1-byte subcommed items - Slot 85
Minor Frame Item Comment
0 s/w version major version #
1 s/w version minor version #
2 head sn# default 0
3 base sn# default 0
4 lis ngood # of LIS Stars
5 blob size in pixels
6 command count # of uplinked commands
7 disk usage %, 0-100

Various 2-byte subcommed items - Slots 86-87
Minor Frame Item Comment
0 triangle count
1 xtab count number of cross-tabulations
2 magnitude zero-point (mmags)
3 magnitude offset (mmags)
4 image mean (slot 86)
image sigma*10 (slot 87)
two 1-byte items
5 blobflux
6 message count # of messages in the downlink queue
7 spare

Various 4-byte subcommed items - Slots 88-91
Minor Frame Item Comment
0 align z1 attitude of ST5000 with respect to the ACS
1 align x
2 align z2
3 yaw window angular half-width of the DAC window
(default is 20 arcminutes for +6V)
4 pitch window angular half-width of the DAC window
(default is 20 arcminutes for +6V)
5 roll window angular half-width of the DAC window
(default is 200 arcminutes for +6V)
6 magnitude window width of the DAC window in V-magnitudes
7 spare

Various 4-byte subcommed items - Slots 92-95
Minor Frame Item Comment
0 shim yaw electronic Shim
1 shim pitch
2 shim roll
3 target RA target Attitude
4 target Dec
5 target roll
6 guide yaw offset to Guide Star
7 guide pitch

Various 4-byte subcommed items - Slots 252-255
Minor Frame Item Comment
0 LIS star catalog size bytes
1 LIS star catalog time seconds since 1970
2 LIS triangle catalog size bytes
3 LIS triangle catalog time seconds since 1970
4 LIS star catalog CRC slots 252-253 (0xb04e)
4 LIS triangle catalog CRC slots 254-255 (0xa951)
5 LIS triangle catalog trim RA used in trimming
6 LIS triangle catalog trim Dec used in trimming
7 LIS triangle catalog trim Radius used in trimming