The following classes implement different MDF version3 blocks.

Channel Class¶

class asammdf.mdf3.Channel(**kargs)¶

CNBLOCK class derived from dict

The Channel object can be created in two modes:

using the file_stream and address keyword parameters - when reading from file
using any of the following presented keys - when creating a new Channel

The keys have the following meaning:

id - Block type identifier, always “CN”
block_len - Block size of this block in bytes (entire CNBLOCK)
next_ch_addr - Pointer to next channel block (CNBLOCK) of this channel group (NIL allowed)
conversion_addr - Pointer to the conversion formula (CCBLOCK) of this signal (NIL allowed)
source_depend_addr - Pointer to the source-depending extensions (CEBLOCK) of this signal (NIL allowed)
ch_depend_addr - Pointer to the dependency block (CDBLOCK) of this signal (NIL allowed)
comment_addr - Pointer to the channel comment (TXBLOCK) of this signal (NIL allowed)
channel_type - Channel type
- 0 = data channel
- 1 = time channel for all signals of this group (in each channel group, exactly one channel must be defined as time channel) The time stamps recording in a time channel are always relative to the start time of the measurement defined in HDBLOCK.
short_name - Short signal name, i.e. the first 31 characters of the ASAM-MCD name of the signal (end of text should be indicated by 0)
description - Signal description (end of text should be indicated by 0)
start_offset - Start offset in bits to determine the first bit of the signal in the data record. The start offset N is divided into two parts: a “Byte offset” (= N div 8) and a “Bit offset” (= N mod 8). The channel block can define an “additional Byte offset” (see below) which must be added to the Byte offset.
bit_count - Number of bits used to encode the value of this signal in a data record
data_type - Signal data type
range_flag - Value range valid flag
min_raw_value - Minimum signal value that occurred for this signal (raw value)
max_raw_value - Maximum signal value that occurred for this signal (raw value)
sampling_rate - Sampling rate for a virtual time channel. Unit [s]
long_name_addr - Pointer to TXBLOCK that contains the ASAM-MCD long signal name
display_name_addr - Pointer to TXBLOCK that contains the signal’s display name (NIL allowed)
aditional_byte_offset - Additional Byte offset of the signal in the data record (default value: 0).

Parameters:

file_stream : file handle

mdf file handle

address : int

block address inside mdf file

Examples

>>> with open('test.mdf', 'rb') as mdf:
...     ch1 = Channel(file_stream=mdf, address=0xBA52)
>>> ch2 = Channel()
>>> ch1.name
'VehicleSpeed'
>>> ch1['id']
b'CN'

Attributes

name	(str) full channel name
address	(int) block address inside mdf file
dependencies	(list) lsit of channel dependencies

Methods

`clear`
`copy`	Generic (shallow and deep) copying operations.
`fromkeys`
`get`
`items`
`keys`
`pop`
`popitem`
`setdefault`
`update`
`values`

ChannelConversion Class¶

class asammdf.mdf3.ChannelConversion(**kargs)¶

CCBLOCK class derived from dict

The ChannelConversion object can be created in two modes:

using the file_stream and address keyword parameters - when reading from file
using any of the following presented keys - when creating a new ChannelConversion

The first keys are common for all conversion types, and are followed by conversion specific keys. The keys have the following meaning:

common keys
- id - Block type identifier, always “CC”
- block_len - Block size of this block in bytes (entire CCBLOCK)
- range_flag - Physical value range valid flag:
- min_phy_value - Minimum physical signal value that occurred for this signal
- max_phy_value - Maximum physical signal value that occurred for this signal
- unit - Physical unit (string should be terminated with 0)
- conversion_type - Conversion type (formula identifier)
- ref_param_nr - Size information about additional conversion data
specific keys
- linear conversion
  b - offset
  
  a - factor
  
  CANapeHiddenExtra - sometimes CANape appends extra information; not compliant with MDF specs
- ASAM formula conversion
  formula - ecuation as string
- polynomial or rational conversion
  P1 .. P6 - factors
- exponential or logarithmic conversion
  P1 .. P7 - factors
- tabular with or without interpolation (grouped by n)
  raw_{n} - n-th raw integer value (X axis)
  
  phys_{n} - n-th physical value (Y axis)
- text table conversion
  param_val_{n} - n-th integers value (X axis)
  
  text_{n} - n-th text value (Y axis)
- text range table conversion
  lower_{n} - n-th lower raw value
  
  upper_{n} - n-th upper raw value
  
  text_{n} - n-th text value

Parameters:

file_stream : file handle

mdf file handle

address : int

block address inside mdf file

Examples

>>> with open('test.mdf', 'rb') as mdf:
...     cc1 = ChannelConversion(file_stream=mdf, address=0xBA52)
>>> cc2 = ChannelConversion(conversion_type=0)
>>> cc1['b'], cc1['a']
0, 100.0

Attributes

address

(int) block address inside mdf file

Methods

`clear`
`copy`	Generic (shallow and deep) copying operations.
`fromkeys`
`get`
`items`
`keys`
`pop`
`popitem`
`setdefault`
`update`
`values`

ChannelDependency Class¶

class asammdf.mdf3.ChannelDependency(**kargs)¶

CDBLOCK class derived from dict

Currently the ChannelDependency object can only be created using the file_stream and address keyword parameters when reading from file

The keys have the following meaning:

id - Block type identifier, always “CD”
block_len - Block size of this block in bytes (entire CDBLOCK)
data - Dependency type
sd_nr - Total number of signals dependencies (m)
for each dependency there is a group of three keys:
- dg_{n} - Pointer to the data group block (DGBLOCK) of signal dependency n
- cg_{n} - Pointer to the channel group block (DGBLOCK) of signal dependency n
- ch_{n} - Pointer to the channel block (DGBLOCK) of signal dependency n
there can also be optional keys which decribe dimensions for the N-dimensional dependencies:
- dim_{n} - Optional: size of dimension n for N-dimensional dependency

Parameters:

file_stream : file handle

mdf file handle

address : int

block address inside mdf file

Attributes

address

(int) block address inside mdf file

Methods

`clear`
`copy`	Generic (shallow and deep) copying operations.
`fromkeys`
`get`
`items`
`keys`
`pop`
`popitem`
`setdefault`
`update`
`values`

ChannelExtension Class¶

class asammdf.mdf3.ChannelExtension(**kargs)¶

CEBLOCK class derived from dict

The ChannelExtension object can be created in two modes:

using the file_stream and address keyword parameters - when reading from file
using any of the following presented keys - when creating a new ChannelExtension

The first keys are common for all conversion types, and are followed by conversion specific keys. The keys have the following meaning:

common keys
- id - Block type identifier, always “CE”
- block_len - Block size of this block in bytes (entire CEBLOCK)
- type - Extension type identifier
specific keys
- for DIM block
  module_nr - Number of module
  
  module_address - Address
  
  description - Description
  
  ECU_identification - Identification of ECU
  
  reserved0’ - reserved
- for Vector CAN block
  CAN_id - Identifier of CAN message
  
  CAN_ch_index - Index of CAN channel
  
  message_name - Name of message (string should be terminated by 0)
  
  sender_name - Name of sender (string should be terminated by 0)
  
  reserved0 - reserved

Parameters:

file_stream : file handle

mdf file handle

address : int

block address inside mdf file

Attributes

address

(int) block address inside mdf file

Methods

`clear`
`copy`	Generic (shallow and deep) copying operations.
`fromkeys`
`get`
`items`
`keys`
`pop`
`popitem`
`setdefault`
`update`
`values`

ChannelGroup Class¶

class asammdf.mdf3.ChannelGroup(**kargs)¶

CGBLOCK class derived from dict

The ChannelGroup object can be created in two modes:

using the file_stream and address keyword parameters - when reading from file
using any of the following presented keys - when creating a new ChannelGroup

The keys have the following meaning:

id - Block type identifier, always “CG”
block_len - Block size of this block in bytes (entire CGBLOCK)
next_cg_addr - Pointer to next channel group block (CGBLOCK) (NIL allowed)
first_ch_addr - Pointer to first channel block (CNBLOCK) (NIL allowed)
comment_addr - Pointer to channel group comment text (TXBLOCK) (NIL allowed)
record_id - Record ID, i.e. value of the identifier for a record if the DGBLOCK defines a number of record IDs > 0
ch_nr - Number of channels (redundant information)
samples_byte_nr - Size of data record in Bytes (without record ID), i.e. size of plain data for a each recorded sample of this channel group
cycles_nr - Number of records of this type in the data block i.e. number of samples for this channel group
sample_reduction_addr - only since version 3.3. Pointer to first sample reduction block (SRBLOCK) (NIL allowed) Default value: NIL.

Parameters:

file_stream : file handle

mdf file handle

address : int

block address inside mdf file

Examples

>>> with open('test.mdf', 'rb') as mdf:
...     cg1 = ChannelGroup(file_stream=mdf, address=0xBA52)
>>> cg2 = ChannelGroup(sample_bytes_nr=32)
>>> hex(cg1.address)
0xBA52
>>> cg1['id']
b'CG'

Attributes

address

(int) block address inside mdf file

Methods

`clear`
`copy`	Generic (shallow and deep) copying operations.
`fromkeys`
`get`
`items`
`keys`
`pop`
`popitem`
`setdefault`
`update`
`values`

DataGroup Class¶

class asammdf.mdf3.DataGroup(**kargs)¶

DGBLOCK class derived from dict

The DataGroup object can be created in two modes:

using the file_stream and address keyword parameters - when reading from file
using any of the following presented keys - when creating a new DataGroup

The keys have the following meaning:

id - Block type identifier, always “DG”
block_len - Block size of this block in bytes (entire DGBLOCK)
next_dg_addr - Pointer to next data group block (DGBLOCK) (NIL allowed)
first_cg_addr - Pointer to first channel group block (CGBLOCK) (NIL allowed)
trigger_addr - Pointer to trigger block (TRBLOCK) (NIL allowed)
data_block_addr - Pointer to the data block (see separate chapter on data storage)
cg_nr - Number of channel groups (redundant information)
record_id_nr - Number of record IDs in the data block
reserved0 - since version 3.2; Reserved

Parameters:

file_stream : file handle

mdf file handle

address : int

block address inside mdf file

Attributes

address

(int) block address inside mdf file

Methods

`clear`
`copy`	Generic (shallow and deep) copying operations.
`fromkeys`
`get`
`items`
`keys`
`pop`
`popitem`
`setdefault`
`update`
`values`

FileIdentificationBlock Class¶

class asammdf.mdf3.FileIdentificationBlock(**kargs)¶

IDBLOCK class derived from dict

The TriggerBlock object can be created in two modes:

using the file_stream and address keyword parameters - when reading from file
using the classmethod from_text

The keys have the following meaning:

file_identification - file identifier
version_str - format identifier
program_identification - program identifier
byte_order - default byte order
float_format - default floating-point format
mdf_version - version number of MDF format
code_page - code page number
reserved0 - reserved
reserved1 - reserved
unfinalized_standard_flags - Standard Flags for unfinalized MDF
unfinalized_custom_flags - Custom Flags for unfinalized MDF

Parameters:

file_stream : file handle

mdf file handle

version : int

mdf version in case of new file

Attributes

address

(int) block address inside mdf file; should be 0 always

Methods

`clear`
`copy`	Generic (shallow and deep) copying operations.
`fromkeys`
`get`
`items`
`keys`
`pop`
`popitem`
`setdefault`
`update`
`values`

HeaderBlock Class¶

class asammdf.mdf3.HeaderBlock(**kargs)¶

HDBLOCK class derived from dict

The TriggerBlock object can be created in two modes:

using the file_stream - when reading from file
using the classmethod from_text

The keys have the following meaning:

id - Block type identifier, always “HD”
block_len - Block size of this block in bytes (entire HDBLOCK)
first_dg_addr - Pointer to the first data group block (DGBLOCK)
comment_addr - Pointer to the measurement file comment text (TXBLOCK) (NIL allowed)
program_addr - Pointer to program block (PRBLOCK) (NIL allowed)
dg_nr - Number of data groups (redundant information)
date - Date at which the recording was started in “DD:MM:YYYY” format
time - Time at which the recording was started in “HH:MM:SS” format
author - author name
organization - organization
project - project name
subject - subject

Since version 3.2 the following extra keys were added:

abs_time - Time stamp at which recording was started in nanoseconds.
tz_offset - UTC time offset in hours (= GMT time zone)
time_quality - Time quality class
timer_identification - Timer identification (time source),

Parameters:

file_stream : file handle

mdf file handle

Attributes

address

(int) block address inside mdf file; should be 64 always

Methods

`clear`
`copy`	Generic (shallow and deep) copying operations.
`fromkeys`
`get`
`items`
`keys`
`pop`
`popitem`
`setdefault`
`update`
`values`

ProgramBlock Class¶

class asammdf.mdf3.ProgramBlock(**kargs)¶

PRBLOCK class derived from dict

The ProgramBlock object can be created in two modes:

using the file_stream and address keyword parameters - when reading from file
using any of the following presented keys - when creating a new ProgramBlock

The keys have the following meaning:

id - Block type identifier, always “PR”
block_len - Block size of this block in bytes (entire PRBLOCK)
data - Program-specific data

Parameters:

file_stream : file handle

mdf file handle

address : int

block address inside mdf file

Attributes

address

(int) block address inside mdf file

Methods

`clear`
`copy`	Generic (shallow and deep) copying operations.
`fromkeys`
`get`
`items`
`keys`
`pop`
`popitem`
`setdefault`
`update`
`values`

SampleReduction Class¶

class asammdf.mdf3.SampleReduction(**kargs)¶

SRBLOCK class derived from dict

Currently the SampleReduction object can only be created by using the file_stream and address keyword parameters - when reading from file

The keys have the following meaning:

id - Block type identifier, always “SR”
block_len - Block size of this block in bytes (entire SRBLOCK)
next_sr_addr - Pointer to next sample reduction block (SRBLOCK) (NIL allowed)
data_block_addr - Pointer to the data block for this sample reduction
cycles_nr - Number of reduced samples in the data block.
time_interval - Length of time interval [s] used to calculate the reduced samples.

Parameters:

file_stream : file handle

mdf file handle

address : int

block address inside mdf file

Attributes

address

(int) block address inside mdf file

Methods

`clear`
`copy`	Generic (shallow and deep) copying operations.
`fromkeys`
`get`
`items`
`keys`
`pop`
`popitem`
`setdefault`
`update`
`values`

TextBlock Class¶

class asammdf.mdf3.TextBlock(**kargs)¶

TXBLOCK class derived from dict

The ProgramBlock object can be created in two modes:

using the file_stream and address keyword parameters - when reading from file
using the classmethod from_text

The keys have the following meaning:

id - Block type identifier, always “TX”
block_len - Block size of this block in bytes (entire TXBLOCK)
text - Text (new line indicated by CR and LF; end of text indicated by 0)

Parameters:

file_stream : file handle

mdf file handle

address : int

block address inside mdf file

text : bytes

bytes for creating a new TextBlock

Examples

>>> tx1 = TextBlock.from_text('VehicleSpeed')
>>> tx1.text_str
'VehicleSpeed'
>>> tx1['text']
b'VehicleSpeed'

Attributes

address	(int) block address inside mdf file
text_str	(str) text data as unicode string

Methods

`clear`
`copy`	Generic (shallow and deep) copying operations.
`from_text`
`fromkeys`
`get`
`items`
`keys`
`pop`
`popitem`
`setdefault`
`update`
`values`

TriggerBlock Class¶

class asammdf.mdf3.TriggerBlock(**kargs)¶

TRBLOCK class derived from dict

The TriggerBlock object can be created in two modes:

using the file_stream and address keyword parameters - when reading from file
using the classmethod from_text

The keys have the following meaning:

id - Block type identifier, always “TX”
block_len - Block size of this block in bytes (entire TRBLOCK)
text_addr - Pointer to trigger comment text (TXBLOCK) (NIL allowed)
trigger_events_nr - Number of trigger events n (0 allowed)
trigger_{n}_time - Trigger time [s] of trigger event n
trigger_{n}_pretime - Pre trigger time [s] of trigger event n
trigger_{n}_posttime - Post trigger time [s] of trigger event n

Parameters:

file_stream : file handle

mdf file handle

address : int

block address inside mdf file

Attributes

address

(int) block address inside mdf file

Methods

`clear`
`copy`	Generic (shallow and deep) copying operations.
`fromkeys`
`get`
`items`
`keys`
`pop`
`popitem`
`setdefault`
`update`
`values`

Channel Class¶

ChannelConversion Class¶

ChannelDependency Class¶

ChannelExtension Class¶

ChannelGroup Class¶

DataGroup Class¶

FileIdentificationBlock Class¶

HeaderBlock Class¶

ProgramBlock Class¶

SampleReduction Class¶

TextBlock Class¶

TriggerBlock Class¶

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