Using frames

Retrieving unconditional frame information

After parsing the LDF into objects the properties of frames defined in the LDF will be accessible.

ldf = parse_ldf('network.ldf')

lsm_frame1 = ldf.get_unconditional_frame('LSM_Frm1')
print(lsm_frame1.frame_id)
>>> 2
print(lsm_frame1.name)
>>> 'LSM_Frm1'
print(lsm_frame1.length)
>>> 2
print(lsm_frame1.publisher)
>>> LinSlave(..)

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Encoding frames

Encoding is the process of the converting the provided LIN Signals into a complete frame.

When encoding there are two options, you can encode raw values and pack them into a frame, or alternatively you can pass the logical values through the signal encoders before packing.

ldf = parse_ldf('network.ldf')

lsm_frame1 = ldf.get_unconditional_frame('LSM_Frm1')
encoded_frame = lsm_frame1.encode_raw(
    {'LeftIntLightsSwitch': 100}
)

When encoding through signal encoders you have the option to pass a list of value converters, otherwise it will use the default encoders assigned through signal representations.

ldf = parse_ldf('network.ldf')

lsm_frame1 = ldf.get_unconditional_frame('LSM_Frm1')
encoded_frame = lsm_frame1.encode(
    {'LeftIntLightsSwitch': 'Off'}
)

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Decoding frames

Decoding is the process of unpacking a LIN frame into the signal values.

Similarly to encoding, you can decode frames into raw signal values or decode them through the signal encoders.

ldf = parse_ldf('network.ldf')

lsm_frame1 = ldf.get_unconditional_frame('LSM_Frm1')
decoded_frame = lsm_frame1.decode_raw(b'\x00')

Just like encoding you can also pass custom value converters and there’s also the option to preserve the unit of physical values, in these cases instead of a floating point value a string will be returned.

ldf = parse_ldf('network.ldf')

lsm_frame1 = ldf.get_unconditional_frame('LSM_Frm1')
decoded_frame = lsm_frame1.decode(b'\x00', keep_unit=True)