Writing Programs for ExpEYES¶
Whether you’re just starting your programming journey, a curious student eager to learn, or an aspiring engineer, this manual will be your trusty companion on this exciting adventure. With our device’s Python library, you’ll discover how to easily conduct experiments, collect data, and gain insights into various physical phenomena, all while having fun and building essential skills.
In the upcoming sections, We’ll walk you through the Python library’s features, using straightforward examples and hands-on exercises. You’ll quickly see how you can create experiments, measure data, and even automate tasks to save time and improve accuracy.
Import and connect¶
the following two lines import the python library, and then attempt to connect to it.
the instance p will now be used to access all the functions of ExpEYES. It is our gateway to the device.
Connecting to the device
from eyes17 import eyes
p = eyes.open()
If connected successfully, p will be automatically initialized. This process also uploads the unique calibration coefficients from the connected device.
In [1]: p
Out[1]: <eyes17.eyes.Interface at 0x7fef91b95120>
Failure to detect a device
If connection fails, Device opening Error will be printed, and the p.connected variable
will be set to False. After properly connecting, you can either recreate p, or call p.__init__()
Simple Test¶
Read A Voltage
from eyes17 import eyes
p = eyes.open()
print(p.get_voltage('A1')
Functions : Accessing the hardware¶
Analog Waveforms Digital Sensors
- Analog Measurements: Voltages, Oscilloscope calls etc
- Voltage Measurement
- Capture calls
- Capture configuration such as trigger, select_range etc
- Code Examples
- Analog Output: Set Voltages
- PV1, PV2
- Waveform Generators: configure sine, triangle, square wave outputs
- sine wave frequency, amplitude, shape configuration
- square wave 1,2 frequency, duty_cycle setting.
- Digital I/O, Timing: Logic Levels, and Timing measurements
- read and set logic levels on digital pins
- timing measurements
- Capacitance, Resistance:
- Measure Capacitance
- Measure Resistance
- I2C Sensors: Read data from sensors
- I2C Function Calls
- Document Sensors
The following is an unsorted list. head over to relevant sections for detailed usage docs and examples
Function call summary
| METHOD | DESCRIPTION |
|---|---|
| get_version | Returns a version string |
| reconnect | reconnect to the device. Needed if the USB cable was replugged |
| guess_sensor | scans the I2C bus, and returns a list of sensor options |
| get_resistance | measure resistance between SEN and GND |
| capture1 | Oscilloscope: Single Channel |
| capture_action | Oscilloscope: Single Channel with an initial action such as set_state |
| capture2 | Oscilloscope: 2 Channels |
| capture4 | Oscilloscope: 4 Channels |
| capture1_hr | Oscilloscope: Single Channel . High Resolution |
| capture_traces | Oscilloscope: Initialization |
| capture_hr_multiple | Oscilloscope: High Res , multiple channels. Sequential Sampling* |
| fetch_trace | Fetch oscilloscope buffer from the hardware |
| oscilloscope_progress | Total samples collected. |
| configure_trigger | trigger level and channel for the oscilloscope |
| set_gain | gain for A1 or A2 inputs |
| select_range | Voltage Range Selection for A1, or A2 . Similar to the range knob on a multimeter |
| get_voltage | measure voltage . Input channel options A1, A2, A3, IN1, SEN |
| get_voltage_time | measure voltage as well as a timestamp. Returns a tuple |
| voltmeter_autorange | autorange the voltmeter |
| get_average_voltage | measure an averaged voltage value |
| get_high_freq | measure high frequencies on IN2 (>100KHz) |
| get_freq | measure frequency on IN2 |
| MeasureInterval | timing measurements for digital signals on IN2 or SEN |
| MeasureMultipleDigitalEdges | timing measurements for digital signals on IN2 or SEN |
| SinglePinEdges | timing measurements for digital signals on IN2 or SEN |
| DoublePinEdges | timing measurements for digital signals on IN2 or SEN |
| get_states | get logic level on inputs SEN, IN2 |
| get_state | get logic level on inputs SEN, IN2 |
| set_state | set output state of OD1 / SQ1 / SQ2 / CS1-4/ |
| stepper_move | Stepper motor movement |
| stepper_forward | Stepper motor movement |
| stepper_reverse | Stepper motor movement |
| set_multiplexer | Set CS1-4 to control analog multiplexers . Only on SEElab3 |
| duty_cycle | measure duty cycle on IN2 |
| r2rtime | Timing measurements on IN2/SEN. Rising Edge to Rising edge |
| f2ftime | Timing measurements on IN2/SEN. Falling Edge to Falling edge |
| r2ftime | Timing measurements on IN2/SEN. |
| f2rtime | Timing measurements on IN2/SEN. |
| multi_r2rtime | Timing measurements on IN2/SEN. Multiple rising edges. |
| set2rtime | Enable an output such as OD1/SQ1, and then measure time to a rising edge on IN2/SEN |
| set2ftime | Enable an output such as OD1/SQ1, and then measure time to a falling edge |
| clr2rtime | Turn off an output such as OD1/SQ1, and then measure time to a rising edge on IN2/SEN |
| clr2ftime | Turn off an output such as OD1/SQ1, and then measure time to a falling edge |
| capacitance_via_RC_discharge | Measure capacitance. For values >1uF |
| get_capacitor_range | estimate capacitance of capacitor connected on IN1-GND |
| get_capacitance | measure capacitance. |
| get_temperature | measure CPU temperature |
| get_ctmu_voltage | - |
| read_bulk_flash | - |
| write_bulk_flash | Do not touch. Especially locations 0,3 which are used to store the calibration coefficients. |
| set_sine | set frequency of sine wave on WG |
| set_wave | set wave type ‘sine’ / ‘tria’ |
| set_sine_amp | set amplitude of the sine wave output on WG |
| load_equation | load an arbitrary waveform to WG using an equation |
| load_table | load a set of 512 points to the wave generator |
| set_sq1 | set frequency of square wave on SQ1 |
| set_sq2 | set frequency of square wave on SQ2 |
| set_sq1_dc | set the duty cycle of the square wave on SQ1 |
| set_sq2_dc | set the duty cycle of the square wave on SQ2 |
| set_pv1 | Set the voltage output on PV1 (-5V to 5V) |
| set_pv2 | Set the voltage output on PV2 (-3V to 3V) |
| servo | Set the angle of a servo motor connected to SQ1 |
| sr04_distance | Measure distance using the SR04 sensor. SQ2→Trig, IN2←ECHO |
| sr04_distance_time | Measure Timestamped distance |
| save | save an array to a csv file |
Static Variables¶
The instance p contains some static variables such as p.version . These are described here
Variable List
- connected: Boolean. Indicates the connection status
- version : A version string read from the connected device. Such as EJ-5.1
- version_number: Version Number
- aboutArray : print(p.aboutArray) to find out
- calibrated : Boolean. Indicates calibration status.
- verbose : set to True to get more verbose information
- WaveType : Indicates if WG output is enabled to sine/tria/arbit shapes.
- WaveMode : ‘sine’/’tria’/’sqr2’ . If sqr2 is enabled, WG output is disabled.
- sinefreq : Last set Frequency of Wave output on WG
- sqr1freq : Last set Frequency of Wave output on SQ1
- sqr1dc : Last set Duty Cycle of Wave output on SQ1
- sqr2freq : Last set Frequency of Wave output on SQ2
- sqr2dc: Last set Duty Cycle of Wave output on WG
Submodules¶
Access to communication buses such as I2C, SPI are available as submodules of the variable p . e.g. p.I2C.scan() returns a list of addresses of sensors/devices connected to the I2C bus.
I2C : Access the I2C Communication bus
- config
- start
- stop
- wait
- send
- send_burst
- restart
- simpleRead
- read
- read_repeat
- read_end
- read_status
- readBulk
- writeBulk
- scan
SPI : Access the SPI Communication bus
- set_parameters
- start
- set_cs
- stop
- send8
- send16
- send8_burst
- send16_burst
- xfer
- map_reference_clock