pyroscience Pico-pH OEM Fiber-Optic pH Meter Instruction Manual
- June 12, 2024
- PyroScience
Table of Contents
- INTRODUCTION
- OVERVIEW
- LOGO-command| The #LOGO-command is sent to the module.| The LED flashes 4
- OPTION 1: OPERATING THE MODULE WITH PYRO WORKBENCH
- OPTION 2: OPERATING THE MODULE WITH PYRO DEVELOPER TOOL
- OPTION 3: SIMPLIFIED CUSTOM INTEGRATION
- LOGO) optionally followed by several input parameters. Input parameters are
- VERS
- LOGO| Examples for a command header
- OPTION 4: ADVANCED CUSTOM INTEGRATION
- TECHNICAL DRAWING
- SPECIFICATIONS
- SAFETY GUIDELINES
- References
- Read User Manual Online (PDF format)
- Download This Manual (PDF format)
Pico-pH
OEM Fiber-Optic pH Meter
MANUAL Version V1.07
www.pyroscience.com
Pico-pH
OEM Fiber-Optic pH Meter
Document Version 1.07
The Pico-pH is released by:
PyroScience GmbH
Hubertusstrasse 35
52064 Aachen
Germany
Phone +49 (0)241 5183 2210
Fax +49 (0)241 5183 2299
Email info@pyroscience.com
Web www.pyroscience.com
Registered: Aachen HRB 17329, Germany
INTRODUCTION
The Pico-pH (item no. PICO-PH) is a fiber-optic OEM meter for read-out of
optical pH sensors from PyroScience. The Pico-pH is characterized by its small
size, durability and low power consumption. This OEM module is easy to
integrate and is controlled with a simple serial communication protocol. To
control the Pico-pH, there are several options depending on the users´ level
of experience with optical sensors:
Option 1 : For initial evaluation purposes, Pico-pH can be operated with
the simple and customer-friendly logger software Pyro Workbench, which is
typically used by end-users. This software offers comfortable settings and
calibration wizards, as well as advanced logging features. Several modules can
be operated in parallel within a single window. This software requires an
encoded USB interface cable (item no. PICO-USB) for connecting the module to a
Windows PC (see chapter 3).
Option 2: For advanced evaluation purposes, the module can be operated
with the software Pyro Developer Tool. It offers simple settings and
calibration procedures, as well as basic logging features. Furthermore,
additional advanced settings offer full control on all features of the module.
This software requires an encoded USB-interface cable (item no. PICO-USB) for
connecting the module to a Windows PC (see chapter 4).
Option 3: A simplified custom integration of the module can be realized
by adjusting the settings and performing sensor calibrations using the
PyroScience software Pyro Workbench or Pyro Developer Tool (requires the
encoded USB interface cable PICO-USB). After closing the software, the
configuration is automatically saved within the internal flash memory of the
module. The module can then be integrated into a specific setup, and your
custom software can perform measurements using a proprietary USB/UART
communication protocol (see chapter 5).
Option 4: For advanced custom integration the full USB/UART communication
protocol is available on request, allowing custom software full control on all
settings, calibration and measurement features of the module (see chapter 6).
OVERVIEW
Figure 1 provides an overview of the Pico-pH. The front provides the port for
connecting an optical fiber used for read-out of optical pH sensors, as well
as solder points for an external temperature sensor enabling automatic
temperature compensation. The backside of the module provides the connector
for the power supply and the digital communication interface, as well as a red
status LED. 2.1 pH sensors
2.1.1 Contactless sensor spots
The optical pH sensor spots (PHSP5) can be mounted in a transparent vessel or
placed directly in front of an optical fiber. For mounting of pH sensor spots,
please refer to the corresponding “Manual pH sensors”. Sensor spots are
connected to the Pico-pH via an
optical fiber. To place the fiber behind the sensor spots on the outside of
the transparent vessel, an adapter (SPADBAS) is necessary. The optical fiber
PICFIB2 can be used for a wall thickness of 0-5 mm. Moreover, rods can be used
instead of fibers when the Pico-pH is placed directly behind the sensor spot.
Depending on the wall thickness of the transparent container, two different
rods can be used. PICROD2 can be used for pH read out through a wall thickness
of 0-5 mm and PICROD3 for a wall thickness of up to 10 mm.
Figure 2: Connection of pH sensor spots to Pico-pH via an optical fiber (left)
or a rod (right).
2.1.2 Flow-through cells
The pH flow-through cells (PHFLOW) can be connected via the optical fiber
PICFIB2 to a Pico-pH. In contrast to the sensor spots, no additional adapter
is needed.
Figure 3: Connection of pH flow-through cell to Pico-pH via an optical fiber.
2.1.3 Vials
pH vials (PHVIAL20) can be connected via the optical fiber PICFIB2 to a Pico-
pH. To connect the optical fiber to the vial, an adapter (ADVIAL20T) is
necessary.Figure 4: Connection of a pH vial
to Pico-pH via an optical fiber.
2.2 Connection of fibers and rods to the optical port
The optical fibers or the fiber rods must be connected to the optical port of
the Pico-pH with their instrument end (IE). At the IE, the core of the optical
fiber protrudes ca. 1 mm from the fiber jacket. The instrument end IE is
marked with “→Instrument” on the ttached label. For PICROD2, the AE is
indicated via a black ring.
For connecting an optical fiber, Pico-pH provides a clamping screw for fibers
and rods. To insert the optical fiber/rod, slightly loosen the nut at the
sensor port of the Pico-pH. Remove the protective cap from the optical
fiber/rod and insert the IE carefully into the sensor port of the Pico-pH
until there is resistance. The insertion length is about 24 mm. Fasten the nut
with your fingers for fixing the fiber/rod.
When using contactless sensors, insert the adapter end (AE) of the optical
fibers/rods into the basic spot adapter, adapter ring or flow-through cell and
fix it with the clamping screw.
2.3 External temperature sensor
The signal of pH sensors is temperature dependent, which can be automatically
compensated. Pico-pH offers a high-precision sensor interface, which can be
directly connected to a Pt100 temperature sensor (not included, item no.
TSUB21-NC). The temperature sensor has to be soldered to the 4 solder pads at
the front of the module. The temperature sensor has to be placed into the
sample of the pH measurements.Figure 5:
Connecting a resistive temperature sensor to the module
The Pt100 temperature sensor has to be soldered to the 4 solder pads at the
front of the module (Figure 5). For short distances (e.g. 10 cm) a simple
2-wire connection might be sufficient. For this, it is important to shortcut
the outer with the inner solder pads as
indicated in Figure 5. For longer distances and/or for high precision
measurements a 4wire connection should be preferred.
In order to minimize potential electrical noise coupling into the external
temperature sensor, the cables should be twisted and kept as short as
possible.
2.4 Status LED
The behavior of the status LED is given in Table 1.
Table 1: Status LED
Status | Description | Behavior of status LED |
---|---|---|
Power-Up | The power supply is switched on. | A correct startup of the module is |
indicated by 4 flashes within 1-2 seconds.
Active| The module is either in idle mode waiting for a new command, or it is
executing a command.| The LED flashes periodically with 1s interval.
Deep sleep| While the power supply is still enabled, the module can be put
into deep sleep mode by the #STOP command.| The LED is switched off.
LOGO-command| The #LOGO-command is sent to the module.| The LED flashes 4
times within 1-2 seconds.
2.5 USB interface cable
For the operation of Pico-pH with a Windows PC, a coded USB interface cable
(item no. PICO-USB) is available from PyroScience. It includes a license for
the comfortable logger software Pyro Workbench and the software Pyro Developer
Tool. Especially for initial testing purposes this software packages can speed
up OEM-developments significantly. Additionally, the USB interface cable PICO-
USB provides a virtual COM-port. Custom software can use this virtual COM-port
for communicating directly with the module based on the communication
protocol.
OPTION 1: OPERATING THE MODULE WITH PYRO WORKBENCH
For initial evaluation purposes the module can be operated with the simple and
customer-friendly software Pyro Workbench, which is typically used by end-
users. This software offers comfortable settings and calibration wizards, as
well as advanced logging features. Several modules can be operated in parallel
within a single window. This software requires an encoded USB interface cable
PICO-USB for connecting the module to a Windows PC. 3.1 Installing the software Pyro Workbenc h
System requirements: PC with Windows 7/8/10 and min. 1000 MB free disk space.
Do not connect the USB-interface cable to your PC before the Pyro Workbench
software has been installed. The software will automatically install the
appropriate USB-drivers.
Installation steps:
- Download the Pyro Workbench from the downloads tab on www.pyroscience.com
- unzip and start the installer and follow the instructions
- connect the interface plug of the USB interface cable to the connector X1 of the Pico-pH
- connect the USB plug to an USB port of the PC. The status LED of the Pico-pH should flash shortly indicating the correct startup of the module.
- Start the Pyro Workbench software.
3.2 Using the software Pyro Workbench
Please refer to the Pyro Workbench manual for general operation instructions
for the software (available on our website).
Please refer to the pH Sensor manual for general information on handling and
calibration of the pH sensors (available on our website).
OPTION 2: OPERATING THE MODULE WITH PYRO DEVELOPER TOOL
For advanced evaluation purposes the module can be operated with the software
Pyro Developer Tool. It offers simple settings and calibration procedures, as
well as basic logging features. Furthermore, additional advanced settings
offer full control on all features of the module. This software requires the
encoded USB interface cable PICOUSB for connecting the module to a Windows
PC. 4.1 Installing the software Pyro
Developer Tool
System requirements: PC with Windows 7/8/10 and min. 1000 MB free disk space.
Do not connect the USB-interface cable to your PC before the Pyro Developer
Tool has been installed. The software will install automatically the
appropriate USB-drivers.
Installation steps:
- Download the Pyro Developer Tool from the downloads tab on www.pyroscience.com
- unzip and start the installer and follow the instructions
- connect the interface plug of the USB interface cable the connector X1 of the Pico-pH
- connect the USB plug to an USB port of the PC. The status LED of the Pico-pH should flash shortly indicating the correct startup of the module.
- Start the Pyro Developer Tool software.
4.2 Using the software Pyro Developer Tool
Please refer to the Pyro Developer Tool manual for general operation
instructions for the software (available on our website).
Please refer to the pH Sensor manual for general information on handling and
calibration of the pH sensors (available on our website).
OPTION 3: SIMPLIFIED CUSTOM INTEGRATION
A simplified custom integration of the module can be realized by adjusting the
settings and performing sensor calibrations using the PyroScience software
Pyro Workbench or the more advanced software Pyro Developer Tool (both
requiring the encoded USB interface cable PICO-USB). After closing the
software, the configuration is automatically saved within the internal flash
memory of the module. The module can then be integrated into a specific setup,
and your custom software can perform measurements using a proprietary USB/UART
communication protocol.
5.1 Configuring the Module using PyroScience Software
Please install either the Pyro Workbench or the Pyro Developer Tool. Follow
chapter 3 or chapter 4, respectively, how to operate the module with the
PyroScience software. Adjust the settings and perform the required
calibrations of the sensor. After the module has been configured, close the
PyroScience software. The configuration is automatically saved within the
internal flash memory. This means that the adjusted settings and the last
sensor calibration are persistent even after a power cycle of the module. Now
the module can be integrated into a customer specific setup via its UART
interface (or via the USB interface cable with its virtual COM port).
5.2 Electrical Connector for Custom Integration
The electrical interface of the Pico-pH consists of the connector X1 (Figure
6). The package includes the fitting connector plug S1 (manufacturer: Phoenix
Contact, type: PTSM0,5/4-P-2,5, Item no.: 1778858). Stripped cable ends can be
connected to S1 without any soldering or crimping. When inserting or removing
a stripped cable end (stripping length 6 mm, max. core diameter 0.5 mm²) into
one of the connector holes of the connector S1, an internal spring mechanism
has to be unlocked. This can be achieved by pushing relatively strongly with a
small screw-driver (flat-bladed 2 mm in width) into the adjacent rectangular
hole (Figure 6). The same manufacturer offers also fitting connector plugs for
PCB mounting (details on request).
Figure 6: Electrical
connectors of Pico-pH
The pin configuration of the connector X1 is given in Table 2.
Table 2: Pin configuration of the connector X1
Pin | Name | Function | Description |
---|---|---|---|
1 | VCC | Power | Power supply |
min. 3.3 VDC
max. 5.0 VDC
2| RXD| Digital input
3.0 V levels (3.3 V & 5 V tolerant)| Data receive line of the UART interface
3| TXD| Digital output 3.0 V levels| Data transmission line of the UART
interface
4| GND| Power| Ground
5.3 Configuration of the Serial Interface
Pico-pH is operated via a serial interface, which is realized as a UART
interface at 3.0 V levels (3.3 V and 5 V tolerant) consisting of a receive and
a transmit line. The configuration of the UART-interface is as follows:
19200 baud, 8 data bit, 1 stop bit, no parity, no handshake
Such an UART interface is very common for microcontrollers or microcontroller
boards (e.g. Arduino or Raspberry Pi). The module can be directly connected to
such UART interfaces without any further interface electronics.
Note: The serial interface of this module is not an RS232 interface. However,
the UART interface can be made compatible to RS232 by integrating an
appropriate “level shifter electronics”.
5.4 Communication Protocol
5.4.1 General Definitions
A command always starts with a specific command header (e.g. MEA, #VERS,
LOGO) optionally followed by several input parameters. Input parameters are
given as human readable decimal numbers, separated by spaces from each other.
Each command must
be terminated by a carriage return. If the command could be successfully
interpreted by the module, the response is sent back to the master after
completion of the requested task. The first part of response consists always
of a copy of the original command, optionally appended with output parameters,
and again terminated by a carriage return.
After a response has been received by the master, the module is immediately
ready for receiving the next command. If the internal processing of the
received command causes any error within the module, the response will be the
error header #ERRO followed by a space and an error code (see below).
Syntax Definitions
MEA
VERS
LOGO| Examples for a command header
---|---
C
S
R| Examples for place holder for signed integer values transmitted as human
readable ASCII strings of decimal numbers. The
absolute maximum range of all values transmitted in the communication protocol
is from -2147483648 to +2147483647
(signed 32bit integer), if not otherwise indicated.
˽| Space (ASCII code 0x20)
↵| Carriage return (ASCII code 0x0D)
5.4.2 MEA – Trigger Measurement
This command triggers a measurement and returns the results.
Command: MEA˽C˽S↵
Response: MEA˽C˽S˽R0˽R1…R17↵
Input Parameters:
C……………Optical channel number. Set C=1.
S………………… If in doubt, then set S to 47!
This parameter defines the enabled sensor types, given as decimal
representation of the following bit field:
Bit 0 (add 1): optical channel
Bit 1 (add 2): sample temperature (typ. the external Pt100sensor)
Bit 2 (add 4): ambient air pressure
Bit 3 (add 8): relative humidity within the module
Bit 4 (add 16): reserved
Bit 5 (add 32): case temperature (temperature within the module)
Example: S = 1 + 2 + 4 + 8 + 32 = 47 means, that the command will trigger the
following measurements: optical channel (pH), sample temperature, case
temperature, ambient air pressure, and relative humidity within the module
housing.
Output Parameters:
R0……….. Returns errors and/or warnings of the last measurement as a decimal
representation of the following bit field. The user has to distinguish between
warnings and errors. A warning indicates, that the measurement results are in
principle still valid, but their precision and/or accuracy might be
deteriorated. An error means, that the respective measurement result is not at
all valid.
Bit 0 (add 1): WARNING – automatic amplification level active
Bit 1 (add 2): WARNING – sensor signal intensity low
Bit 2 (add 4): ERROR – optical detector saturated
Bit 3 (add 8): WARNING – reference signal intensity too low
Bit 4 (add 16): ERROR – reference signal too high
Bit 5 (add 32): ERROR – failure of sample temperature sensor (e.g. Pt100)
Bit 6 (add 64): reserved
Bit 7 (add 128): WARNING high humidity (>90%RH) within the module
Bit 8 (add 256): ERROR – failure of case temperature sensor
Bit 9 (add 512): ERROR – failure of pressure sensor
Bit 10 (add 1024): ERROR – failure of humidity sensor
Example: R0 = 34 = 2 + 32 means, that there is a warning about low signal
intensity of the optical sensor, and that the external temperature sensor
(Pt100) had a failure.
If R0 = 0 then no error or warning appeared.
R1…R17 The results of the measurement given as 17 values. The most
important result values are highlighted.
| Name| Unit| Description
---|---|---|---
R1| -reserved-| m°| Phase shift of optical measurement (raw data)
R2-R4| dphi| |
R5| tempSample| 0.001 °C| Sample temperature (typ. external Pt100 sensor)
R6| tempCase| 0.001 °C| Case temperature (internal T-sensor within module)
R7| signalIntensity| 0.001 mV| Signal intensity of the optical measurement
R8| ambientLight| 0.001 mV| Ambient light entering the sensor
R9| pressure| 0.001 mbar| Ambient air pressure
R10| humidity| 0.001 %RH| Relative humidity within the module housing
R11| resistorTemp| 0.001 Ohm| Resistance of the temperature sensor (raw data)
R12
R13| -reserved-| |
R14| ph| 0.001| pH value measured by optical pH sensors
R15
R17| -reserved-| |
This command is the essential command for triggering measurements. If the
input parameter S is requesting several sensor types to be measured, the
optical pH measurement (“optical channel”) is always performed as the last
measurement. This ensures that for enabled automatic temperature compensation
the sample temperature measurement (typ. external Pt100) is done before it is
then used for compensating the pH measurement.
IMPORTANT: If automatic temperature compensation is enabled for the
optical sensor, it is mandatory to enable Bit1 of the input parameter S! The
output parameters pH and tempSample give the results of the pH measurement and
of the temperature measurement (typ. external Pt100).
The output parameter signalIntensity is a measure of the signal quality
(“signal intensity”) of the connected optical pH sensor. As a rule of thumb,
typical values will be in the range of 20-500 mV. Low signal intensities (<50
mV) might lead to noisy pH measurements. A low signal intensity might be an
indicator that the pH sensor is not configured optimally and/or that the pH
sensor is “worn out”/depleted and has to be replaced. Please note, that the
signal intensity is also dependent on the actually measured pH value. Low pH
values have a high signal intensity, high pH values have a lower signal
intensity.
The output parameter ambientLight is a measure how much ambient infrared light
is entering the pH sensor. In principle, such ambient light is not influencing
the pH measurement. However, excess ambient light might lead to a saturation
of the optical detector (indicated by an enabled ERROR Bit2 in R0), which will
lead to an invalid pH measurement. As a rule of thumb, the sum of
signalIntensity and ambientLight should be kept below ca. 2000 mV (the optical
detector saturates around 2500 mV).
Example Communication:
Command MEA˽1˽3↵
Response MEA˽1˽3˽0˽30120˽0˽0˽0˽20135˽0˽87016˽11788˽0˽0˽123022˽0˽0˽7105˽0˽0˽0↵
This example command triggers the measurement of the sample temperature (typ.
external Pt100) and of the optical pH sensor. The highlighted output
parameters of the shown example response are interpreted as follows:
R0 = 0 → No error or warning occurred; the measurement is valid!
tempSample = 20.135 °C
signalIntensity = 87.016 mV
ambientLight = 11.788 mV
pH = 7.105
5.4.3 CPH – Calibrate pH Sensor
This command is used for calibrating the pH sensor at up to 3 different
calibration points. The sensor must be calibrated at 2 points and a pH offset
adjustment is possible for advanced users. In contrast to electrochemical pH
sensors, optical pH sensors are calibrated outside of the dynamic range where
the pH indicator is either fully protonated or fully deprotonated. The first
calibration point is called “low pH calibration” and is performed using a
highly acidic buffer (pH 2, item no. PHCAL2). As second calibration point,
“high pH calibration” is performed using a highly basic buffer (pH 10.00, item
no. PHCAL10 or pH 11, item no. PHCAL11). After these two calibration points,
the sensor is ready to use.
“Offset calibration point” adds an offset to the pH output. This offset has to
be determined using a well-known buffer at the pH value of the pKa of the
sensor (e.g. a buffer with pH 8 must be used for -PK8 sensors). It is highly
advised to read the pH sensor manual for more details on the calibration
(equilibration time, salinity, which buffers must not be used, etc.…).
Command: CPH˽C˽N˽P˽T˽S↵
Response: CPH˽C˽N˽P˽T˽S↵
Input Parameters:
C | Optical channel number. Set C=1 |
---|---|
N | Calibration point type. |
N=0: low pH calibration point
N=1: high pH calibration point
N=2: offset calibration point
P| pH value of calibration standard in units of 10-3 pH (e.g. 3000 means pH 3
T| Temperature of the calibration standard in units of 10 -3 °C (e.g. 20000
means 20°C)
S| Salinity of the calibration standard in units of 10 -3 g/L (e.g. 1000 means
1 g/L)
This command performs 16 repeated optical measurements, and uses the average
for the calibration. The total duration for this procedure varies between ca.
3s and ca. 6s depending on the configuration of the module. In order to keep
the calibration permanently even after a power cycle, the command SVS must be
executed afterwards.
5.4.4 SVS – Save Configuration Permanently in Flash Memory
This command is used for storing the current configuration in the flash
memory:
Command: SVS˽C↵
Response: SVS˽C↵
Input Parameters:
C……………Optical channel number. Set C=1.
Saves the actual settings and calibration as the new default values into the
internal flash memory. These default values are automatically loaded after a
power cycle.
Example Communication:
Command: SVS˽1↵
Response: SVS˽1↵
5.4.5 #VERS – Get Device Information
This command returns general information about the device.
Command: #VERS↵
Response: #VERS˽D˽N˽R˽S˽B˽F↵
Output Parameters:
D………………………… Device ID, identifies the specific device type. For the Pico-pH
the device ID is always 4.
N …………………………..Number of optical channels. For the Pico-pH this value is 1.
R………………………….Firmware version, e.g. R=403 designates firmware version 4.03
S ………………………………Bit field about available sensor types and supported optical
analytes as follows:
Bit 0-7: Available Sensor Types | Bit 8-15: Supported Optical Analytes |
---|---|
Bit 0: optical channel(s) | Bit 8: oxygen |
Bit 1: sample temperature (typ. Pt100) | Bit 9: optical temperature |
Bit 2: pressure | Bit 10: pH |
Bit 3: humidity | Bit 11: CO2 |
Bit 4: analog in | Bit 12: reserved |
Bit 5: case temperature | Bit 13: reserved |
Bit 6: reserved | Bit 14: reserved |
Bit 7: reserved | Bit 15: reserved |
Example: S = 1 + 2 + 4 + 8 + 32 + 1024 = 1071 means, that the device provides
an optical channel as well as sample and case temperature, pressure, and
humidity sensors, and the optical channel supports the analytes pH.
B ……………………..Firmware build number starting at 1 for each firmware version
(reflects minor firmware revisions which normally do not require a software or
firmware update for the user)
F …………………..Bit field about available features as follows:
Bit 0: analog out 1 | Bit 5: battery |
---|---|
Bit 1: analog out 2 | Bit 6: stand-alone logging |
Bit 2: analog out 3 | Bit 7: sequence commands |
Bit 3: analog out 4 | Bit 8: user memory |
Bit 4: user interface (display, buttons) | Bit 9-31: reserved |
Example: F = 1 + 2 + 4 + 8 + 256 = 271 means that 4 analog outputs are
supported and the module possesses a user memory. Note, the optionalanalog
outputs require additional hardware (more information on request).
Example Communication:
Command: #VERS˽1↵
Response: #VERS˽1˽4˽403˽1071˽2˽271↵
5.4.6 #IDNR – Get Unique ID Number
This command returns the unique identification number of the respective
device.
Command: #IDNR↵
Response: #IDNR˽N↵
Output Parameters:
N ……………. Unique ID number. Note, this parameter is given as an unsigned 64 bit
integer!
Returns the unique identification number of the device (does NOT correspond to
the serial number of the device).
Example Communication:
Command: #IDNR↵
Response: #IDNR˽2296536137892833272↵
5.4.7 #LOGO – Flash Status LED
This command lets the status LED flash for 4 times within ca. 1 s.
Command: #LOGO↵
Response: #LOGO↵
This command can be used to check proper communication with the device. Or it
might be helpful in setups with more than one device, in order to identify
which COM port is connected to which device.
5.4.8 #PDWN – Power Down Sensor Circuits
This command switches off the power supply of the sensor circuits.
Command: #PDWN↵
Response: #PDWN↵
This command can be used for some power saving during idle operation periods.
Note, that the sensor circuits are automatically powered up again, if the
module receives any command (e.g. MEA) requiring a sensor measurement. This is
also the case if a broadcast measurement takes place.
5.4.9 #PWUP – Power Up Sensor Circuits
This command switches on the power supply of the sensor circuits.
Command: #PWUP↵
Response: #PWUP↵
The wake-up duration is up to 250 ms.
5.4.10 #STOP – Enter Deep Sleep Mode
This command puts the device into a deep sleep mode with very low power
consumption
Command: #STOP↵
Response: #STOP↵
During deep sleep mode the device has very low power consumption). No standard
communication via USB/UART is possible. The deep sleep mode can be only exit
by sending a
5.4.11 #RSET – Reset Device
This command triggers a reset of the device.
Command: #RSET↵
Response: #RSET↵
Triggers a reset of the device, as if the device experienced a power cycle.
5.4.12 #RDUM – Read User Memory
This command reads values from the user memory registers.
Command: #RDUM˽R˽N↵
Response: #RDUM˽R˽N˽Y0…YN↵
Input Parameters:
R……………..Address of first register to be read from the user memory (0…63)
N……………..Total number of registers to be read (1…64)
Output Parameters:
Y0…YN ………..Content of the requested user memory registers (signed 32bit
integers).
The device offers a user memory of altogether 64 signed 32bit integer numbers
(range 2147483648 to 2147483647) which is located in the flash memory and is
therefore retained even after power cycles. This read command returns N
(N=1…64) consecutive values Y1 … YN from the user memory starting at the user
memory address R (R=0…63). Note, that N+R must be <=64. The content of the
user memory has no influence on the module itself. It can be used for any user
specific purpose.
Example Communication:
Command: #RDUM˽12˽4↵
Response: #RDUM˽12˽4˽-40323˽23421071˽0˽-555↵
This example shows a command which requests the values of 4 consecutive
beginning with the user memory address 12.
5.4.13 #WRUM – Write User Memory
This command writes values into the user memory registers.
Command: #WRUM˽R˽N˽Y0…YN↵
Response: #WRUM˽R˽N˽Y0…YN↵
Input Parameters:
R……………….Address of first user memory register to be written (0…63)
N………….Total number of registers to be written (1…64)
Y0…YN ……………….Values to be written to the user memory registers (signed
32bit integers).
This command writes N (N=1…64) values Y1 … YN consecutively starting at the
user memory address R (R=0…63). Note, that N+R must be <=64. This command must
be used economically, because the flash memory is designed for typ. max. 20000
flash cycles.
Each time this command is executed, it will trigger a flash cycle.
Example Communication:
Command: #WRUM˽0˽2˽-16˽777↵
Response: #WRUM˽0˽2˽-16˽777↵
This example shows a command which writes the value -16 into the memory
address 0, and the value 777 into the memory address 1.
5.4.14 #ERRO – Response if Error Occurred
If an error occurred, the device will give the following response:
Command: any command
Response: #ERRO˽C ↵
This error response is mostly given, if the master did not send the command
with the correct communication syntax. The output parameter C represents the
general PyroScience error types as given by the following table.
Note: Warnings and errors directly related to the sensor measurements
(e.g. a broken Pt100 temperature sensor, or a “worn out” optical pH senor)
will not result in such an #ERRO response. Instead, such warning and errors
are given in the output parameter R0 of the MEA command (see above).
C | Error Type | Description |
---|---|---|
-1 | General | A non-specific error occurred. |
-2 | Channel | The requested optical channel does not exist. |
-11 | Memory Access | Memory access violation either caused by a not existing requested register, or by an out of range address of the requested value. |
-12 | Memory Lock | The requested memory is locked (system register) and a write access was requested. |
-13 | Memory Flash | An error occurred while saving the registers permanently. The SVS request should be repeated to ensure a correct permanent memory. |
-14 | Memory Erase | An error occurred while erasing the permanent memory region for the registers. The SVS request should be repeated. |
-15 | Memory Inconsistent | The registers in RAM are inconsistent with the permanently stored registers after processing SVS. The SVS request should be repeated. |
-21 | UART Parse | An error occurred while parsing the command string. The last command should be repeated. |
-22 | UART Rx | The command string was not received correctly (e.g. device was not ready, last request was not terminated correctly). Repeat the last command. |
-23 | UART Header | The command header could not be interpreted correctly (must contain only characters from A-Z). Repeat the last command. |
-24 | UART Overflow | The command string could not be processed fast enough to prevent an overflow of the internal receiving buffer |
-25 | UART Boudrote | The requested baudrate is not supported. No baudrate change took place. |
-26 | UART Request | The command header does not match any of the supported commands. |
-27 | UART Start Rx | The device was waiting for incoming data: however, the next event was not triggered by receiving a command. |
-28 | UART Range | One or more parameters of the command are out of range. |
-30 | I2C Transfer | There was an error transferring data on the 12C bus. |
-40 | Temp Ext | The communication with the sample temperature sensor was not successful. |
-41 | Periphery No Power | The power supply of the device periphery (sensors, SD card) is not switched on. |
5.5 Available Implementations of Communication Protocol
We offer libraries for controlling Pico-pH using LabView programming language.
The libraries and corresponding documentation are free for download from our
website.
OPTION 4: ADVANCED CUSTOM INTEGRATION
For advanced custom integration the full USB/UART communication protocol is available on request, allowing custom software full control on all settings, calibration and measurement features of the module.
TECHNICAL DRAWING
The solder pads have 2.54mm pitch.
SPECIFICATIONS
General Specifications|
---|---
Dimensions| L=59 mm. 0 17mm (without the optical port)
Weight| ca. 20 g
Power supply| min. 3.3 VDC max. 5.0 VDC
Connector plug| Phoenix Contact PTSM0.5/4-13- 2 E.
Power consumption|
-during operation| typ. 10 mA
-during deep sleep mode| typ. <100 tth (<10 LiA on request)
Start-up time|
-from power off| 1-2 s
-from deep sleep| ca. 200 ms
Interface| UART (3.0V levels. 5V tolerant).
19200 baud. 8 data bit. 1 stop bit. no parity. no handshake
Max. sample rate’| ca. 10 samples/s
Operating temperature| 0 to 50 °C
Storage temperature| -20 to 70 °C
Max. relative humidity| Non-condensing conditions
pH Sensor| Refer to the separately available specifications for the connected
pH sensor
---|---
Port for External Temperature Sensors
Compatible sensor types| Pt100
Measurement principle| 2-wire or 4-wire resistance measurement via 24bit ADC
Resolution| <0.02 C
Accuracy| <+-0.2 C
Range| -30 to 150 t
Internal Temperature Sensor| (located on internal PCB)
Resolution| 0.02 -C
Accuracy| +-0.3 °C
Range| -40 to 125 °C
Note: This max. sample rate refers only to the limits of the UART communication. It doesnot consider the actual response time of the connected optical pH sensor or of the temperature sensor.
SAFETY GUIDELINES
Before using the Pico-pH and its sensors, read carefully the instructions and
user manuals.
In case of problems or damage, disconnect the instrument and mark it to
prevent any further use. Consult PyroScience for advice. There are no
serviceable parts inside the device. Please note that opening the housing will
void the warranty.
The Pico-pH is not watertight. The Pico-pH should be kept under dry and clean
conditions, avoiding moisture, dust, corrosive conditions and excessive
heating of the instrument (e.g. direct sun light).
Calibration and application of the sensors is on the user’s authority, as well
as data acquisition, treatment and publication.
The sensors and the Pico-pH are not intended for medical, aerospace or
military purposes or any safety-critical applications.
The sensors should be used in the laboratory by qualified personnel only,
following the user instructions and the safety guidelines of the manual, as
well as the appropriate laws and guidelines for safety in the laboratory.
Keep the sensors and the Pico-pH out of reach of children.
CONTACT
PyroScience GmbH
Hubertusstraße 35
52064 Aachen
Deutschland
Tel.: +49 (0)241 5183 2210
Fax: +49 (0)241 5183 2299
info@pyroscience.com
www.pyroscience.com
References
Read User Manual Online (PDF format)
Read User Manual Online (PDF format) >>