Main module

This is the module that handles all the communication with the current Gramophone device.

Gramophone class

class Gramophone.Gramophone(device, verbose=False)

Representation of a Gramophone device.

Parameters:

• device (usb.core.Device) – The USB device.
• verbose (bool) – If set to True the details of the communication are printed.

class Parameter(name, info, type)

info

Alias for field number 1

name

Alias for field number 0

type

Alias for field number 2

decode_payload(param_id, payload)

Decodes the given payload based on the type of the parameter.

Parameters:

• param_id (int) – The key for the parameter dict. See: Gramophone.parameters
• payload (list) – The payload that will be decoded

decode_response(response)

Decodes a response. Returns the error message if the command was not successful and None otherwise.

Parameters:response – The response to decode. Ptype response:Packet

ping()

Send a ping packet with 5 bytes and print the time the process took.

read_analog_out()

Read the voltage of the analog output.

Returns:The voltage the analog output is set to. Return type:float

read_dev_state()

Read the state of the device. The device should be in 0x01 state for usage. The 0x00 state is for setup.

Returns:The device state. ‘Application’ or ‘IAP’ Return type:str

read_firmware_info()

Read the firmware information from the Gramophone. Sets the fimware related variables of the object.

Returns:A dictionary with the firmware info fields in a human readable format. Return type:dict

read_homing_position()

The home postion that can be found by homing.

Returns:The position Return type:int

read_homing_state()

Reads wheter the device is homing. A home position can be set and this value changes when it is reached. 0 if the encoder is not trying to find the home position, 1 if it is homing and 2 if the home position was found.

Returns:0, 1 or 2 dependin on the state Return type:int

read_input(input_id)

Read the state of a digital input.

Parameters:input_id (int) – The number of the digital input (1 or 2) Returns:0 if the input is low, 1 if it is high Return type:int

read_inputs()

Read the state of all digital inputs.

Returns:dict with input numbers as keys, and their states as values. eg: {1:1, 2:1} when both inputs are high Return type:dict

read_linmaze_params()

Read the parameters for the LineMaze module. Time, position, and IO combined.

Retruns:A dict with the read parameters, with ids as keys Return type:dict

read_output(output_id)

Read the state of a digital output.

Parameters:output_id (int) – The number of the digital output (1 to 4) Returns:0 if the output is low, 1 if it is high Return type:int

read_outputs()

Read the state of all digital outputs.

Returns:dict with output numbers as keys, and their states as values. eg: {1:0, 2:0, 3:0, 4:0} when both outputs are low Return type:dict

read_param(param_id)

Read a single parameter and return its value.

Parameters:param_id (int) – The id of the parameter that should be read. Returns:The value of the parameter Return type:depends on the parameter, see: Gramophone.parameters

read_params(combo_id)

Read multiple parameters and return them in a dict.

read_position()

Read the position register of the Gramophone.

Returns:The position in counts travelled (1 full rotation = 14400 counts) Return type:int

read_product_info()

Read the product information from the Gramophone. Sets the product related variables of the object.

Returns:A dictionary with the product info fields in a human readable format. Return type:dict

read_recorder_params()

Read the parameters for the Recorder module. Time, velocity, and IO combined.

Retruns:A dict with the read parameters, with ids as keys Return type:dict

read_sensors()

Read the values from the voltage and temperature sensors.

Returns:A dict with the parameter ids as keys. See: Gramophone.parameters Return type:dict

read_temperatures()

Read the values from the temperature sensors.

Returns:A dict with the parameter ids as keys. See: Gramophone.parameters Return type:dict

read_time()

Read the time from the Gramophone’s clock

Returns:Time in ms/10 Return type:int

read_velocity()

Read the velocity of the Gramophones disk. Velocity is averaged in a window with a set size.

Returns:Velocity in counts/sec (1 full rotation = 14400 counts) Return type:

read_voltages()

Read the values from the voltage sensors.

Returns:A dict with the parameter ids as keys. See: Gramophone.parameters Return type:dict

read_window_size()

Read the window size of the velocity calculation, ie. how many position differences are averaged to get the velocity. Larger windows result in smoother velocity but slower response.

Retruns:The window size Return type:int

reset()

Reset the device. Returns None if successful and the error string otherwise.

reset_position()

Reset the Gramophone’s internal position counter to 0.

reset_time()

Reset the Gramophone’s internal clock to 0.

send(packet)

Sends a Packet to the device.

Parameters:packet – The Packet to send. Ptype packet:Packet

stop_burst(port)

Stop turning the given port on and off. see: start_burst

Parameters:port (int (1-4)) – The port that will stop being turned on and off

write_analog(value)

Set the analog output to the given voltage, eg. to 2.1 V

Parameters:value (float) – The voltage that will be set.

write_output(output, value)

Set the given output to a given state, eg. output 1 to 1 (high).

Parameters:

• output (int) – The output to set (1 to 4)
• value (int) – The state to set (1 is high, 0 is low)

write_param(param, payload)

Write the given payload into the given parameter.

Helper classes

class Gramophone.Packet(target, source, cmd, payload, msn=None)

A 64 byte data packet that can be sent to the Gramophone.

Parameters:

• target ([int, int]) – 2 byte address of the target. source of the reply given to this packet
• source ([int, int]) – 2 byte address of the source. target of the reply given to this packet
• cmd (int) – Identifier of the command
• payload (list of ints) – The payload for the command eg.: the value to write
• msn (int) – Any number. The reply packet’s msn will be the same.

class Gramophone.GramophoneError

Exception for Gramophone related communication errors.