Memorandum
Results of testing laboratory models of the experiments DP made by the Space Research Institute of the
Bulgarian Academy of Sciences, with KFKI RMKI DUCU-BSTM Simulator in September 7th through September
10th 2004.
Important hardware parameters of interface, which are the followings:
1.
Pinouts of plugs of sockets,
DP voltage and power consumption,
were checked and finalized during previous meeting in June.
2. Bulgarian side gave a new requirements for DACU attached to this protocol. It contains different telecommands to
set operation modes of DP. These commands will be sent to BSTM, DACU during flight. KFKI-RMKI can
implement requirements in BSTM, DACU software until November.
3. The telemetry format and protocol were tested. Communications parameters of DP were changed which are:
words with eight data bits, two stop bits, and no parity. Transmission speed is 38400 Baud. In communication test
DP software worked with some failure, meaning loss in data transmission and sometime DP software stopped
forwarding scientific data packets. The transmission loss, were approximately 10%.
To fix transmission failures the KFKI-RMKI can help Bulgarian side if they ask to supply them with Linux Real
Time Operational System and Simulation Software running on DUCU-BSTM Simulator. In case of such a request,
the Bulgarian side has to provide the necessary hardware.
4. The participants agreed to continue interface test in the begin of November, when KFKI-RMKI solved new
requirements given in point 2.
Budapest, 10 September 2004
Ditchko Batchvarov
Sándor Szalai
Kálmán Balajthy
János Nagy
DP/LP COMMUNICATON MESSAGES
1. Format of the COMMUNICATION MESSAGES
a) Packet structure
00
01
02
03
04
….
n+4
n+5
SOH (=1) start of packet
Length of data(n-1)
Message type
STX (=2) start of data
Data bytes
Data bytes
Data bytes
EOT(=03)
b) General Message types
01
02
81
82
HK (no science)
Science data
HK (indicates science)
Science (more science)
c) Additional Message types
04
08
84
88
Set Operation mode
Set parameters values
Set Operation mode ( indicates
science)
Set parameters values (indicates
science)
2.Message packets (from DACU to Device Unit):
b) Activate Global Mode
c) Set Experiment Parameter
d) Request HK packet
e) Request Science packet
1
1
1
1
0
1
5
0
4
8
1
2
3. Answer Data Packets (from Device Unit to DACU):
2
2
2
2
2
mode_byte
parameter
byte
[GMT{ymdHMS} 6 bytes ]
0x20
3
3
3
3
a) Housekeeping
b) Science
c) Other answers
1
1
1
0xff
0xff
0xff
0x(8)1*
2
0x(8)2**
2
0x(8)<c>*** 2
[…256bytes house keeping data]
[…256 bytes science data]
[...256 bytes house keeping]****
3]
3
3
Notes:
(*) 1 byte value (0x01 or 0x81)
(**) 1 byte value (0x02 or 0x82)
(***) 1 byte value (0x<c> or 0x8<c>), where <c> is one of the digits 4 (for the requests "Reset
DP CPU", "Activate Global Mode" or "Activate "Setting of parameters"") or 8 (for the request
"Set Experiment Parameter").
(****) The answer form (3.c) has to be save into "house-keeping file", as control_log data.
4. Global Mode values-(2.b):
( used into “Set global mode” ((2b) above))
Codes:
Comments:
0xd0
(Basic mode of experiment)
0xd1
0xd2
(Speedy(Research) mode of the experiment)
(Adaptive mode of the experiment)
Notes:
After sending the request "Activate Global Mode" from DACU to DEVICE UNIT the DEVICE
UNIT is starting (for this mode.) It supposes, that the correspond parameters was setting, before
this message is received. The Device Unit is working in this mode while new Activate Global
Mode wasn’t received.
The modes of experiments are present into “Activate Global Mode” command with a byte on 4-th
position, consisting one of the numbers 0xd0,0xd1 or 0xd2.
5. Setting of Experiment parameters:
Each of the Experiment parameters has unique number and a value. Before activation of the
experiment mode, the correspond parameters must have assigned values. The Experiment
parameters are setting with command (2.c). After restart the parameters have own default values.
The parameter are enumerated with parameter numbers: 0 – 7.
The parameter values are 2 bytes unsigned integers. (low byte, high byte).
Into command line the parameter and value are present by bytes 4,5 and 6. (4 byte consists
parameter number, 5 low byte of parameter value,6 high byte of parameter value).
There are defined next parameters for the different experiment modes:
3
Experiment modes
Basic mode
Fast(Research) mode
Adaptive mode
Parameter number
0x00
Length (in bytes)
2
0x01
2
0x02
2
0x03
2
0x04
2
0x05
2
0x06
2
0x07
2
Note
The length of average
period in units (10 ms).
It has to be unsigned
integer..
The
number
of
protected
electrode
assigned to this period.
The value has to be 0,1
or 2
The length of average
period in units (10 ms).
It has to be unsigned
integer..
The
number
of
protected
electrode
assigned. The value
has to be 0,1 or 2
The length of average
period in units (10 ms).
It has to be unsigned
integer..
The
number
of
protected
electrode
assigned. The value
has to be 0,1 or 2
The bound value firing
speedy mode.
It has to be a 2 bytes
unsigned integer.
The adaptation mode.
It has to be a 2 bytes
unsigned integer
6.Format of the data fields into Housekeeping commands
Housekeeping commands are Activate Global Mode, Set experiment Parameter and Request HK
packet with correspond codes 0x04,0x08 and 0x02. Each of them includes Data field, prepared
from DACU and is followed by a answer from DU. DACU is writing the answer into House
Keeping Data file. Here are present only the communication parts of Data fields of these
commands. Other fields aren’t connected with the communication and are experiment depended.
6.1. Request HK packet.
The input from DACU includes field of Date time as 6 bytes presents smhDMY GMT.
The output (to DACU) message includes 256 bytes, divided into two identical parts. Each of
them begins with 5 bytes, presenting the time of the last Request HK packet sending or 0( if there
4
not exists this one).The first 4 bytes present the time interval from current year begin in units of
10 ms. (first byte low, last byte high ).The 5-th byte presents the year as a number 0-for 2005,1
for 2006,2 for 2007 and 3 for 2008. The next 2 bytes present the current time offset from the
moment of the last HK by the clock of DU. The next ,7-th byte from Data field, presents ms*10
units of this offset. The next 2 bytes present the current validity of the experiment parameters.
Their positions are bytes 8 and 9 and are denoted Cmode and Cpar (8 and 9)*.Cmode and Cpar
have to be zeroed if the parameters are correct. If any of them isn’t zero, DACU has to send
parameter and mode values before starting of new mode processing.
6.2 Set experiment Parameter
The input from DACU includes Data field of 3 bytes. The first presents parameter number, the
second low byte of the parameter level, the last high byte of parameter value.
The output (to DACU) message includes 256 bytes, divided into two identical parts. Each of
them begins with 2 bytes, presenting Cmode and Cpar respectively. Their positions are bytes 0
and 1 into Data field...Cmode and Cpar have to be zeroed if the parameters are correct. If any of
them isn’t zero, DACU has to send parameter and mode values before starting of new mode
processing.
6.3 Activate Global Mode
The input from DACU includes Data field of 1 byte. It presents experiment mode(d0,d1 or d2)..
The output (to DACU) message includes 256 bytes, divided into two identical parts. Each of
them begins with 2 bytes, presenting Cmode and Cpar respectively. Their positions are bytes 0
and 1 into Data field...Cmode and Cpar have to be zeroed if the parameters are correct. If any of
them isn’t zero, DACU has to send parameter and mode values before starting of new mode
processing.
*Cmode value may be 0 or 1, dependedly if the current experiment mode is valid(0) or no(1).
Cpar coresponds bit by bit (from bit 0 to bit 7) to the parameters number 0-7.
If corespond bit is 0, the parameter is valid. 1 denotes invalid parameter.
5