py-lab-hal 2.3.20240715

Description:

pylabhal 2.3.20240715

Python Laboratory Hardware Abstraction Layer, Py-Lab-HAL
Py-Lab-HAL is a multi-platform Python library for Lab Test Equipment Control
and Automation. It has been run and tested under Windows, Linux, and Mac.
We support some common and uncommon lab test equipment:

DC Power Supply
Battery Emulator
DMM
Electronic Load
Function Generator
Light Panel
Power Meter
Generic USB Relay
Remote Power Switch
Oscilloscope
SMU
Spectroradiometer
Stepper Motor
Temperature Chamber
Robot Arm

Py-Lab-HAL also supports multiple equipment interfaces:

Serial
VXI-11
USB
Socket
HiSLIP (Coming Soon...)

Requirements

OS: Windows, Mac, or Linux
Python 3.9+
NI-VISA if running on Windows

Download Here



Installation
py-lab-hal is on PyPI, and it's installable via pip.
pip install py-lab-hal

For linux users, you will have to run an extra step:
echo "SUBSYSTEM==\"usb\", MODE=\"0666\", GROUP=\"usbusers\"" | sudo tee -a /etc/udev/rules.d/99-usbusers.rules

to configure your USB device access or you won't be able to see instruments over
an USB connection. You might have to restart the computer after entering the
command.
Getting Started
Let's get our basic imports out of the way:
from py_lab_hal import builder
from py_lab_hal.cominterface import cominterface

The builder helps us build the instrument while cominterface defines the
communication interface in which the host/test computer will use to talk to the
test equipment.
Creating the Builder
Creating the builder is a simple one-liner:
build = builder.PyLabHALBuilder()

Configuring the cominterface
Since Py-Lab-HAL is supporting various interfaces, there are quite a lot of
parameters to set up across each interface. For details, check out the source.
To see what is connected to your system and their resource data, you can use our
built-in utility in a terminal:
python3 -m py_lab_hal.scan

This will scan and list out all the visa_resources available to your system.
Configuring USB and VXI-11
An USB or VXI-11 connection is straight-forward,
just fill in the visa_resource you need:
build.connection_config = cominterface.ConnectConfig(
visa_resource='USB0::10893::769::MY59006118::0::INSTR',
)

Configuring Socket
For Socket connections, you will need to know the
socket_host and socket_port of your instrument. This will be filled into
an addition config, NetworkConfig, which you can define separately, or
in-line as we have done here:
build.connection_config = cominterface.ConnectConfig(
network=cominterface.NetworkConfig(
host='192.168.11.11',
port=5025,
),
)

Configuring Serial
Setting up serial connection is the most involved as it contains
the most parameters. As in socket, you will need to fill out an addition config,
SerialConfig. If you are using all default values, then you can just pass in
SerialConfig as is, if not, you will need to set it up. The parameters and
their defaults are as follows:

Baud Rate

Default = 9600



cominterface.SerialConfig(baud_rate = 9600)


Data Bits

Default = 8



cominterface.SerialConfig(data_bits = 8)


Stop Bits

Default = 1 or cominterface.StopBits.ONE
Select from:



cominterface.StopBits.ONE
cominterface.StopBits.ONE_POINT_FIVE
cominterface.StopBits.TWO

#Usage
cominterface.SerialConfig(stop_bits = cominterface.StopBits.ONE)


Parity

Default = 'N' or cominterface.Parity.NONE
Select from:



cominterface.Parity.EVEN
cominterface.Parity.NONE
cominterface.Parity.SPACE
cominterface.Parity.MARK
cominterface.Parity.ODD

#Usage
cominterface.SerialConfig(parity = cominterface.Parity.NONE)


Flow Control

Default = 0 or 'cominterface.ControlFlow.NONE'
Select from:



cominterface.ControlFlow.DTR_DSR
cominterface.ControlFlow.RST_CTS
cominterface.ControlFlow.NONE
cominterface.ControlFlow.XON_XOFF

#Usage
cominterface.SerialConfig(flow_control = cominterface.ControlFlow.RST_CTS)

A small example of overriding some of the default values when setting up
SerialConfig:
build.connection_config = cominterface.ConnectConfig(
visa_resource='ASRL/dev/ttyUSB0::INSTR',
serial_config=cominterface.SerialConfig(
baud_rate=115200,
flow_control=cominterface.ControlFlow.RST_CTS,
),
)

Build the Instrument Object
Now that the builder has been instantiated and cominterface setup, it is time to
build and instantiate the actual instrument!
But first we need to make sure our initalization call to the instrument is
set up correctly:
Instrument Config
The instrument configuration and their defaults are listed below:
build.instrument_config.reset = True
build.instrument_config.clear = True
build.instrument_config.idn = True
build.instrument_config.auto_init = True

reset, clear, and idn are standard VISA SCPI commands, while auto_init
is a Py-Lab-HAL command. The first 3 commands and their SCPI equivalents are as
follows:

reset = *RST
clear = *CLR
idn = *IDN?

auto_init determines whether to open a connection to the instrument after
builder instantiates the object. If you select false, you will have to issue a
separate call to open a connection to the instrument.

Note: reset, clear, and idn only applies to VISA SCPI instruments.
For non-VISA
instruments, all 3 of these flags must be set to False or you will get an error
with the instrument. A few examples of a non-VISA instrument would be:
robot arm, panel light, temp chamber, and generic USB relay.

Build Instrument
To finish building the instrument, we will invoke the build_instrument
function:
build.build_instrument(builder.FOLDER_NAME.MODULE_NAME)

Where:

FOLDER_NAME = The type of equipment, e.g., DMM, DC Power Supply, etc.
MODULE_NAME = The module or model name of the instrument, e.g., Keysight,
Tektronix, Lecroy, etc. The MODULE_NAME follows the convention of
MAKER_MODEL, for example: KEYSIGHT_N6705C in all caps.

Usage:
dcpsu = build.build_instrument(builder.DCPowerSupply.KEYSIGHT_N6705C)
dmm = build.build_instrument(builder.DMM.AGILENT_34465A)

For details on putting it all together, see the example below and
our demo folder for more examples.
Example
import time
from py_lab_hal import builder
from py_lab_hal.cominterface import cominterface

build = builder.PyLabHALBuilder()

build.connection_config = cominterface.ConnectConfig(
visa_resource='USB0::10893::769::MY59006118::0::INSTR',
)
dmm = build.build_instrument(builder.DMM.AGILENT_34465A)

build.connection_config = cominterface.ConnectConfig(
visa_resource='ASRL/dev/ttyUSB0::INSTR',
serial_config=cominterface.SerialConfig()
)
dcpsu = build.build_instrument(builder.DCPowerSupply.GWIN_PST3202)

try:
dcpsu.set_output(1, 5, 1)
dcpsu.enable_output(1, True)
print('output 5 V')
time.sleep(1)
for i in range(5):
print(dmm.read())

dcpsu.set_output(1, 6, 1)
dcpsu.enable_output(1, True)
print('output 6 V')
time.sleep(1)
for i in range(5):
print(dmm.read())

finally:
dmm.close()
dcpsu.close()

Disclaimer
This is not an official Google product.