Headers

Datex Header

All requests use this header:

Byte No	Description
1	Start flag: FRAMECHAR
2	(start of header) Total length = 0031h = 49d bytes (word r_len)
3
4	Reserved, set to zero (byte res1)
5	Ignored by monitor, set to zero (byte r_dri_level)
6	Reserved = 0000H (byte res2[2])
7
8	Transmission time = 0x00000000, ignored by monitor when sending transmission request (dword r_time). However, time can be meaningful in outputted messages, which use the header of the same structure (dword r_time).
9
10
11
12	Reserved = 00000000H (dword res3)
13
14
15
16	Main type of record = DRI_MT_PHDB = 0 (r_maintype)
17
18	Offset to the first subrecord = 0000H (sr_desc[0].offset)
19
20	Type of first subrecord, DRI_PH_XMIT_REQ = 0 (sr_desc[0].sr_type)
21	Offset to the second subrecord = 0000H, calculated from the beginning of the data area after the header part. Value is not meaningful, since there is only one subrecord in the request (sr_desc[1].offset).
22
23	“No more subrecords” (sr_desc[1].sr_type)
24	sr_desc[2].offset = 000, no meaning since only one subrecord transmitted. sr_desc[2].sr_type, no meaning
25
26
27	sr_desc[3].offset = 000, no meaning sr_desc[3].sr_type, no meaning
28
29
30	sr_desc[4].offset = 000, no meaning sr_desc[4].sr_type, no meaning
31
32
33	sr_desc[5].offset = 000, no meaning sr_desc[5].sr_type, no meaning
34
35
36	sr_desc[6].offset = 000, no meaning sr_desc[6].sr_type, no meaning
37
38
39	sr_desc[7].offset = 000, no meaning sr_desc[7].sr_type = 0, no meaning
40
41

class pycollect.headers.DatexHeaderRequest(*args, **kwargs)

Bases: pycollect.headers.HeaderHandler

Header for request transfer.

This header is the combination of Datex Header and the follow header:

Byte No	Description
42	Request current values of physiological database = DRI_PH_DISPL (field phdb_rcrd_type of struct phdb_req)
43	Transmission interval in seconds = 00A, i.e., send current values of physiological database every 10 seconds (field tx_interval of struct phdb_req)
44
45	reserved[0] of struct phdb_req, must be zeroed
46
47	reserved[1] of struct phdb_req, must be zeroed
48
49	reserved[2] of struct phdb_req, must be zeroed
50
51	Checksum
52	End flag: FRAMECHAR

class pycollect.headers.DatexHeaderResponse(*args, **kwargs)

Bases: pycollect.headers.HeaderHandler

The data transmitted from monitor is writed in this header.

This header is the combination of Datex Header and the follow header, is used for store the waveforms inputs.

Byte No	Description
42-1491	Data
1492	Checksum
1493	End flag: FRAMECHAR

class pycollect.headers.DatexHeaderWaveRequest(*args, **kwargs)

Bases: pycollect.headers.HeaderHandler

Header for request wave transfer.

This header is the combination of Datex Header and the follow header, is user for create the recuest of waveforms.

Byte No	Description
42	Request type: one of WF_REQ_CONT_START, WF_REQ_CONT_STOP or WF_REQ_TIMED_START.
43
44	Duration of snapshot
45
46-53	An array of the requested waveform subrecords. There is room for up to 8 waveforms, but the monitor sends only the waveforms that fit within the 600 samples/s limitation and ignores the rest. The type array must be terminated using the DRI_EOL_SUBR_LIST constant (0xFF), unless there are 8 waveforms is the request.
54-73	Reserved
74	Checksum
75	End flag: FRAMECHAR

class pycollect.headers.HeaderHandler(data=None, init=None, size=None)

Bases: object

Header Handler.

Establish a way to read and write GE protocol headers.

__getitem__(element)

Return value from header.

Parameters:element (str) – Define de index and the format of requested value. Returns:Target element, could be of many types due to the nested suported format. Return type:int, list, HeaderHandler

Note

recursive format:

header[‘basic:ecg:hr’]

reverse the byte array before to read:

header[‘-basic:ecg:hr’]

return the byte array without convert to integer:

header[‘basic:ecg:hr,’]

return the boolean for the bit 4:

header[‘basic:ecg:hr:4]

return the integer generated with the bits 0 to 5:

header[‘basic:ecg:hr:0-5]

__init__(data=None, init=None, size=None)

Parameters:

• data (array) – Load an array to build the header.
• init (OrderedDict) – Initialize the the data header with this values.
• size (str) – Define the size in bytes of the current header.

__length__(header)

Calculate the bytes length of the current header.

Parameters:header (dict) – Target header in dict format for calculate the size. Returns:Number of bytes used by the header. Return type:int

array()

Return the sorted byte array with the correct size.

If one element is defined as 2 bytes length, this must be splitted and completed (if necessary) with an empty byte.

Returns:Single array with data header values, linke in C, C++, C#. Return type:list

load(data)

Load the data into the current header values.

Parameters:data (array) – Load an array to build the header.

request()

Generate the final header.

Returns:The main data with start-flag, checksum and end-flag. Return type:list

set(element, value)

Modify the value of one header element.

Parameters:

• element (str) – Header element.
• value (str) – New value for element.

to32bits(value)

Convert a value into a 32 bits array.

Parameters:value (array, int) – A length 4 array or integer value, if integer then it will be converted to [0, 0, 0, value]. Returns:List of 32 bits that represents the input value. Return type:list

class pycollect.headers.PhysiologicalData(*args, **kwargs)

Bases: pycollect.headers.HeaderHandler

The data transmitted from monitor is writed in this header.

This header is the combination of Datex Header and the follow header, is used for store the requested subrecords.

Byte No	Description
0-4	Time
5-274	basic subclass
275-544	ext1 subclass
545-814	ext2 subclass
815-1084	ext3 subclass
1085	Marker, contains the number of latest entered mark.
1086	contains control information for patient data management functions, used internally by the monitor.
1087-1088	The last word of the subrecord, contains The physiological data record class. The current D-O Record Interface level. The subrecord type.