PICO PicoLog CM3 Manual

Programmer's Guide
plcm3pg r4
Current Data Logger
PicoLog®CM3

IPicoLog CM3 Data Logger Programmer's Guide
Copyright © 2011–2019 Pico Technology Ltd. All rights reserved. plcm3pg r4
Contents
1 Introduction .............................................................................................................................. 1
1 Overview ............................................................................................................................................................................ 1
2 Legal information ............................................................................................................................................................ 1
3 Minimum PC requirements ........................................................................................................................................... 2
2 Driver information ................................................................................................................... 3
1 About the driver ................................................................................................................................................................ 3
2 PLCM3CloseUnit .............................................................................................................................................................. 4
3 PLCM3Enumerate ........................................................................................................................................................... 5
4 PLCM3GetUnitInfo .......................................................................................................................................................... 6
5 PLCM3GetValue .............................................................................................................................................................. 7
6 PLCM3IpDetails ............................................................................................................................................................... 8
7 PLCM3OpenUnit .............................................................................................................................................................. 9
8 PLCM3OpenUnitViaIp .................................................................................................................................................. 10
9 PLCM3SetChannel ........................................................................................................................................................ 11
10 PLCM3SetMains ......................................................................................................................................................... 12
11 Constants and enumerated types .......................................................................................................................... 13
Index .......................................................................................................................................... 15

PicoLog CM3 Data Logger Programmer's Guide 1
Copyright © 2011–2019 Pico Technology Ltd. All rights reserved. plcm3pg r4
1 Introduction
1.1 Overview
The PicoLog CM3 is a three-channel, high-resolution data logger for use with
current clamps.
This manual explains how to use the API (application programming interface)
functions, so that you can develop your own programs to collect and analyze
data from the data logger.
Additional information
For instructions on connecting and using the device, and setting it up with the PicoLog software, please see:
PicoLog CM3 Data Logger User's Guide
A selection of code examples is available from repositories under the "picotech" organization on GitHub.
1.2 Legal information
The material contained in this release is licensed, not sold. Pico Technology Limited grants a license to the
person who installs this software, subject to the conditions listed below.
Access. The licensee agrees to allow access to this software only to persons who have been informed of these
conditions and agree to abide by them.
Usage. The software in this release is for use only with Pico products or with data collected using Pico products.
Copyright. Pico Technology Ltd. claims the copyright of, and retains the rights to, all material (software,
documents, etc.) contained in this SDK except the example programs. You may copy and distribute the SDK
without restriction, as long as you do not remove any Pico Technology copyright statements. The example
programs in the SDK may be modified, copied and distributed for the purpose of developing programs to collect
data using Pico products.
Liability. Pico Technology and its agents shall not be liable for any loss, damage or injury, howsoever caused,
related to the use of Pico Technology equipment or software, unless excluded by statute.
Fitness for purpose. As no two applications are the same, Pico Technology cannot guarantee that its equipment
or software is suitable for a given application. It is your responsibility, therefore, to ensure that the product is
suitable for your application.
Mission-critical applications. This software is intended for use on a computer that may be running other software
products. For this reason, one of the conditions of the license is that it excludes use in mission-critical
applications, for example life support systems.
Viruses. This software was continuously monitored for viruses during production, but you are responsible for
virus-checking the software once it is installed.
Support. If you are dissatisfied with the performance of this software, please contact our technical support staff,
who will try to fix the problem within a reasonable time. If you are still dissatisfied, please return the product and
software to your supplier within 14 days of purchase for a full refund.
Upgrades. We provide upgrades, free of charge, from our web site at www.picotech.com. We reserve the right to
charge for updates or replacements sent out on physical media.

Introduction2
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Trademarks. Windows is a trademark or registered trademark of Microsoft Corporation. Pico Technology Limited
and PicoLog are internationally registered trademarks.
1.3 Minimum PC requirements
To ensure that your PicoLog CM3 operates correctly, you must have a computer with at least the minimum
system requirements to run one of the supported operating systems, as shown in the following table. The
performance of the data logger will be better with a more powerful PC. Please note that the PicoLog software is
not installed as part of the SDK.
Item
Specification
Operating system
Windows 7, Windows 8 or Windows 10
32-bit and 64-bit versions supported
Processor
As required by the operating system
Memory
Free disk space
Ports
USB and optional Ethernet ports

PicoLog CM3 Data Logger Programmer's Guide 3
Copyright © 2011–2019 Pico Technology Ltd. All rights reserved. plcm3pg r4
2 Driver information
2.1 About the driver
The Pico Technology software development kit (PicoSDK) is available in 32-bit and 64-bit versions and contains
the drivers for the PicoLog CM3.
The API is supplied as a Windows dynamic link library (DLL), plcm3.dll, which can be found in the lib
subdirectory of your SDK installation and allows you to program a PicoLog CM3 using standard C function calls.
The Windows DLL exports the function definitions in standard C format but this does not limit you to
programming in C; you can use the API with any programming language that supports standard C calls.
Two applications can access the PicoLog CM3 at the same time, one through the USB port and one through the
Ethernet port, with each application having its own instance of the driver with its own handle. In this configuration,
power must be supplied by the USB port and not by Power over Ethernet.
These are the routines in the driver:
· PLCM3CloseUnit - Close the port (do this each time you finish using the device!)
· PLCM3Enumerate - Get list of attached devices
· PLCM3GetUnitInfo - Get the batch number and serial number, or the calibration date, of this PicoLog CM3
· PLCM3GetValue - Get the most recent data reading from a channel
· PLCM3IpDetails - Read or write IP settings
· PLCM3OpenUnit - Open the device through its USB interface
· PLCM3OpenUnitViaIp - Open the device through its Ethernet interface
· PLCM3SetChannel - Specify the sensor type and filtering for a channel
· PLCM3SetMains - Change the mains noise filtering setting to 60 Hz. The default is 50 Hz.
The normal calling sequence for these routines is as follows:
1. Load driver
2. Open driver
3. Set channels
4. While you want to read data
5. Get data
6. End while
7. Close unit
8. Unload driver (happens automatically when you terminate the application)

Driver information4
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2.2 PLCM3CloseUnit
PICO_STATUS PLCM3CloseUnit
(
int16_t handle
)
This routine disconnects the driver from the device.
Arguments:
handle, identifies the device to close
Returns:
defined in PicoStatus.h

PicoLog CM3 Data Logger Programmer's Guide 5
Copyright © 2011–2019 Pico Technology Ltd. All rights reserved. plcm3pg r4
2.3 PLCM3Enumerate
PICO_STATUS PLCM3Enumerate
(
int8_t * details,
uint32_t * length,
PLCM3_COMMUNICATION_TYPE type
)
This routine returns a list of all the attached PicoLog CM3 devices of the specified port type.
Arguments:
details, a string buffer to receive a maximum of length characters. The string is a
comma-separated list of attached devices of the selected type. The buffer must be long
enough to accommodate the expected string.
USB devices are listed in this format:
USB:Serial Number
Example: USB:DV045/055
Ethernet devices are listed in this format:
IP:Serial Number[IP Address:port]
Example: IP:DV045/055[192.168.1.253:6500]
length,
input:
the length of the string buffer
output:
the length of the information string returned
type, the communication type used by the PicoLog CM3. Can be any of the following
enumerated types:
PLCM3_CT_USB = 0x00000001
PLCM3_CT_ETHERNET = 0x00000002
PLCM3_CT_ALL = 0xFFFFFFFF
Returns:
defined in PicoStatus.h

Driver information6
Copyright © 2011–2019 Pico Technology Ltd. All rights reserved.plcm3pg r4
2.4 PLCM3GetUnitInfo
PICO_STATUS PLCM3GetUnitInfo
(
int16_t handle,
int8_t * string,
int16_t stringLength,
int16_t * requiredSize,
PICO_INFO info
)
This routine obtains information on a specified device.
Arguments:
handle, identifies the device whose information is required
string, output: the information requested
stringLength, input: the length of the string buffer
requiredSize, output: the length of the information string requested. If this is longer
than stringLength then only the first stringLength characters of the requested
information are written to string.
info, the type of information required. The following types are defined in PicoStatus.h:
PICO_DRIVER_VERSION
PICO_USB_VERSION
PICO_HARDWARE_VERSION
PICO_VARIANT_INFO
PICO_BATCH_AND_SERIAL
PICO_CAL_DATE
PICO_KERNEL_DRIVER_VERSION
PICO_MAC_ADDRESS
Returns:
defined in PicoStatus.h

PicoLog CM3 Data Logger Programmer's Guide 7
Copyright © 2011–2019 Pico Technology Ltd. All rights reserved. plcm3pg r4
2.5 PLCM3GetValue
PICO_STATUS PLCM3GetValue
(
int16_t handle,
PLCM3_CHANNELS channel,
int32_t * value,
)
Once you open the driver and define some channels, the driver begins to take continuous readings from the
PicoLog CM3. When you call this routine, it immediately sets data to the most recent reading for the specified
channel.
Arguments:
handle, identifies the device from which to get data
channel, the number of the channel to read, from 1 to 3
value, output: an array where the sample values will be stored
Returns:
defined in PicoStatus.h

Driver information8
Copyright © 2011–2019 Pico Technology Ltd. All rights reserved.plcm3pg r4
2.6 PLCM3IpDetails
PICO_STATUS PLCM3IpDetails
(
int16_t handle,
int16_t * enabled,
int8_t * ipaddress,
uint16_t * length,
uint16_t * listeningPort,
PLCM3_IP_DETAILS_TYPE type
)
This routine either reads or writes the IP details of a specified device. The type argument controls whether the
operation is a read or a write.
Arguments:
handle, identifies the device that is the operation target
enabled, input: 1 to enable the device, 0 to disable
output: 1 if the device is enabled, 0 if disabled
ipaddress, input or output: the IP address of the device
length, input or output: the length of the IP address string
listeningPort, input: the size of the string array specified in ipaddress to receive
the IP address string.
output: the length of the IP address string
type, the type of operation to be performed. Can be either of the following
types:
PLCM3_IDT_GET, to read information from the driver
PLCM3_IDT_SET, to write information to the driver
Returns:
defined in PicoStatus.h

PicoLog CM3 Data Logger Programmer's Guide 9
Copyright © 2011–2019 Pico Technology Ltd. All rights reserved. plcm3pg r4
2.7 PLCM3OpenUnit
PICO_STATUS PLCM3OpenUnit
(
int16_t * handle,
int8_t * serial
)
This routine obtains a handle for the PicoLog CM3 device with the given serial number.
If you wish to use more than one device, you must call the routine once for each of them.
Arguments:
handle, output: handle of the device that was opened. This value is used to identify the
device in all further function calls.
serial, input: serial number string of device, null-terminated.
Returns:
defined in PicoStatus.h

Driver information10
Copyright © 2011–2019 Pico Technology Ltd. All rights reserved.plcm3pg r4
2.8 PLCM3OpenUnitViaIp
PICO_STATUS PLCM3OpenUnitViaIp
(
int16_t * handle,
int8_t * serial,
int8_t * ipAddress
)
This routine obtains a handle for the Ethernet-connected PicoLog CM3 device, identified by either its IP address
or its serial number.
· Using IP address identification, a device anywhere on the internet or local network can be opened.
· Using serial number identification, only a device on the local network can be opened.
If you wish to use more than one PicoLog CM3, you must call the routine once for each device.
Arguments:
handle, output: handle of the device that was opened. This value is used to identify the
device in all further function calls.
serial, input: serial number of device as a null-terminated string, or a null pointer if
ipAddress is used.
ipAddress, input: the IP address of the device as a null-terminated string, or a null pointer
if serial is used.
String format: <ipaddress>:<port>
Returns:
defined in PicoStatus.h

PicoLog CM3 Data Logger Programmer's Guide 11
Copyright © 2011–2019 Pico Technology Ltd. All rights reserved. plcm3pg r4
2.9 PLCM3SetChannel
PICO_STATUS PLCM3SetChannel
(
int16_t handle,
PLCM3_CHANNELS channel,
PLCM3_DATA_TYPES type,
)
This routine configures a single channel of the specified PicoLog CM3. It can be called any time after calling
PLCM3OpenUnit.
The fewer channels selected, the more frequently they will be updated. Measurement takes around 720 ms per
active channel.
Arguments:
handle, identifies the device to be configured
channel, which channel you want to set the details for. It should be between 1 and 3.
type, the type of reading you require. Choose from the table below.
Returns:
defined in PicoStatus.h
PLCM3_DATA_TYPES
Data type
PLCM3_OFF
0
disable channel
PLCM3_1_MILLIVOLT
1
1 mV range (1 mV/A)
PLCM3_10_MILLIVOLTS
2
10 mV range (10 mV/A)
PLCM3_100_MILLIVOLTS
3
100 mV range (100 mV/A)
PLCM3_VOLTAGE
4
(µV)

Driver information12
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2.10 PLCM3SetMains
PICO_STATUS PLCM3SetMains
(
int16_t handle
uint16_t sixty_hertz
)
This routine is used to inform the driver of the local mains (line) frequency. This helps the driver to filter out
electrical noise.
Arguments:
handle, identifies the device to be configured
sixty_hertz, for 50 Hz set to 0; for 60 Hz set to 1
Returns:
defined in PicoStatus.h

PicoLog CM3 Data Logger Programmer's Guide 13
Copyright © 2011–2019 Pico Technology Ltd. All rights reserved. plcm3pg r4
2.11 Constants and enumerated types
typedef enum enPLCM3Channels
{
PLCM3_CHANNEL_1 = 1,
PLCM3_CHANNEL_2,
PLCM3_CHANNEL_3,
PLCM3_MAX_CHANNELS = PLCM3_CHANNEL_3
} PLCM3_CHANNELS;
typedef enum enPLCM3DataType
{
PLCM3_OFF,
PLCM3_1_MILLIVOLT,
PLCM3_10_MILLIVOLTS,
PLCM3_100_MILLIVOLTS,
} PLCM3_DATA_TYPES;
typedef enum enIpDetailsType
{
PLCM3_IDT_GET,
PLCM3_IDT_SET,
} PLCM3_IP_DETAILS_TYPE;
typedef enum enCommunicationType
{
PLCM3_CT_USB = 0x00000001,
PLCM3_CT_ETHERNET = 0x00000002,
PLCM3_CT_ALL = 0xFFFFFFFF
} COMMUNICATION_TYPE;

PicoLog CM3 Data Logger Programmer's Guide 15
Copyright © 2011–2019 Pico Technology Ltd. All rights reserved. plcm3pg r4
Index
B
Batch number 6
C
Calibration date 6
Channel setup 11
Closing a unit 4
COMMUNICATION_TYPE type 13
D
Driver version 6
E
Ethernet port 10
H
Handle, obtaining 9
Hardware version 6
I
IP address 10
IP details 8
IP_DETAILS_TYPE type 13
K
Kernel driver version 6
L
Legal information 1
M
Mains frequency 12
O
Opening a unit 9
P
PC requirements 2
PLCM3_CHANNELS type 13
PLCM3_DATA_TYPES type 13
PLCM3CloseUnit 4
PLCM3Enumerate 5
PLCM3GetUnitInfo 6
PLCM3GetValue 7
PLCM3IpDetails 8
PLCM3OpenUnit 9
PLCM3OpenUnitViaIp 10
PLCM3SetChannel 11
PLCM3SetMains 12
S
Serial number 6
U
USB 2
USB version 6
V
Variant information 6

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PE19 8YP
United Kingdom
Copyright © 2011–2019 Pico Technology Ltd. All rights reserved.
plcm3pg r4 2019-11-05
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United States
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Tel: [phone]
USA regional office:UK headquarters:
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www.picotech.com
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