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Data_Logger_Fundamentals.pdf (application/pdf Objeto) Sdi12-xbee-bridge - Project Hosting on Google Code. OWL2/BASIC Stamp to Unidata water level & SDI-12. Unidata float and capacitance water level gages note on SDI-12 protocol (c) 1998 , 2002 EME Systems, Berkeley CA U.S.A. Contents (updated 11/13/2010) We use the following BS2 subroutine to read data from the HSIO (High Speed I/O, serial data interface) of the model 6531 depth gage manufactured by Unidata of Australia. This professional (US$500) instrument uses a float and counterweight on a beaded line to measure depths of up to 49 meters with a resolution of 0.75 millimeter.

The U6531 is wired to the logger using three of the digital i/o lines. Uss_ con 12 ' pin to activate the serial interfaceuclk_ con 13 ' pin to clock the serial interfaceudata_ con 14 ' pin to receive data from sensorresult var wordU6541: high uss_ ' activate the sensor pause 9 ' delay for settling shiftin udata_,uclk_,lsbpre,[udata\16] ' grab the data low uss_ ' deactivate the sensor debug dec result,cr ' show the result nap 6 ' wait a bitgoto U6541 ' do it again The data is returned in the word variable, result. . Building an Environmental Monitoring System for SDI-12 Devices. With the release of the LabVIEW SDI-12 API, LabVIEW has the ability to interface with thousands of environmental monitoring sensors that communicate via the SDI-12 protocol. This whitepaper will discuss the specifications of the protocol and applications in which the protocol is used.

We will then provide an in-depth description of the LabVIEW SDI-12 API and illustrate how to create a customizable, software-defined SDI-12 communication system. 1. Introduction Back to Top 2. The SDI-12 Protocol Overview SDI-12 stands for Serial Data Interface at 1200 baud. In SDI-12 applications, communication takes place on the bidirectional serial data line and occurs between SDI-12 instruments (sensors) and a data recorder.

Industry Applications for the SDI-12 Protocol 3. The LabVIEW SDI-12 API allows users to easily communicate with any SDI-12 instrument. Hardware and Software You’ll Need LabVIEW NI LabVIEW is the industry-leading software tool for test, measurement, and control applications. SDI-12 Sensor. SDI-12 Sensor Engine. The SDI-12 Problem Although SDI-12 is a cryptic hardware and software protocol, it is still a widely used standard interface between environmental sensors and data loggers. Until now, sensor vendors have had the difficult and costly burden of creating their own SDI-12 solutions from scratch. Because of the many eccentricities of the SDI-12 protocol, it is a difficult task to create a truly compliant SDI-12 sensor interface.

The SDI-12 Sensor Translator Figure 1 - SDI12 Sensor Translator Sample Board. (Custom foot prints available, for large quantity orders.) Vegetronix has solved the problem of interfacing sensors to the SDI-12 bus by creating a small SDI12 Sensor Translator board which contains all of the necessary functionality. Figure 2 shows a connection diagram for utilizing the SDI-12 Sensor Translator. Figure 2 - SDI12 Sensor Translator Connection Diagram. Because of its small size the sensor can often be incorporated into the sensor housing. Applications Features Example: out= 2*x+3, FAIRCHILD SEMICONDUCTOR|74LCX125MTC|Buffer Logic IC | Farnell España. Dedicated hardware RS232 to SDI-12 controller? AVR Freaks General Electronics - Dedicated hardware RS232 to SDI-12 controller? Nkinar - Aug 21, 2009 - 10:09 PMPost subject: Dedicated hardware RS232 to SDI-12 controller? Hello-- I've been reading the book "Principles of Electrical Measurement" by Sławomir Tumański, and on page 399, the author mentions that it is possible to create a bridge between RS232C and the SDI-12 protocol using what appears to be a specialized IC.

I am wondering if such an IC is available, or if it would be possible to implement SDI-12 using the RX and TX pins of a USART shorted together. Kartman - Aug 22, 2009 - 12:45 AMPost subject: RE: Dedicated hardware RS232 to SDI-12 controller? The TX signal would need to be open collector - that is it can only pull down. Nkinar - Aug 22, 2009 - 01:55 AMPost subject: RE: Dedicated hardware RS232 to SDI-12 controller? Sure, sounds good, Kartman. An example schematic can be found at the website in the SDI-12 spec document. Jim Thanks, Jim. Thanks, Jim. Thanks, Jim. Búsqueda de productos | Farnell España. Búsqueda de productos | Farnell España.

TBS02A SDI-12 to Analog Converter Module. SDI-12 Bus Interface. SDI-12 Bus Interface See our other Circuits. SDI-12 is a arcane protocol used in environmental sensing. It consists of 2 wires: data and ground and runs at 1200 baud. The bus is bidirectional, and the logger is the master, and the sensors are slave devices on the bus. It's not a very easy protocol to implement. Fortunately, you can purchase translators from Vegetronix which all easy implementation of the SDI-12 protocol.

They have SDI-12 to RS232 translators and SDI-12 to USB translators for computer interfaces, and also analog to SDI-12 translators to convert any sensor into an SDI-12 compliant device. This simple circuit interfaces a 3.3V microcontroller with a 1200 baud UART to the SDI-12 bus. SDI-12 Bus Interface Schematic Do you need help with an electronics design? [Employment] [Downloads][Articles] [Contact Us] TEXAS INSTRUMENTS|SN74LVC1G240DBVR|IC, INVERTING BUFFER, SOT-23-5 | Farnell España.