Implementar protocolo de comunicação serial UART no LabVIEW

Boa Tarde,
Estou querendo implementar o protocolo de comunicação serial UART no LabVIEW.
A descrição do projeto é mais ou menos essa:
- Uma Interface no LabVIEW para receber o dados enviados pela serial UART;
- Uma DAQ NI USB-6212 irá receber o dado por um pino digital ou analógico (a princípio estou usando um pino analógico);
- Um microcontrolador que envia dados através da serial UART;
- Sistema operacional Windows 7;
Estou querendo implementar o protocolo de comunicação pelos motivos:
- Usei o Visa da comunicação serial e um cabo USB-Serial genérico, mas não consegui taxas de recepção rápidas como eu preciso, quando eu tentava transmitir dados de forma mais rápida, eles chegavam corrompidos;
- O exemplos que encontrei do protocolo implementado usam o LabVIEW FPGA, e pelo que eu li minha placa de aquisição (NI USB-6212) não suporta FPGA.
Tem algum exemplo ou sugestão de como devo proceder.
Desde já agradeço.
Atenciosamente,
Fernando Esquírio Torres

Good morning, Fernando,
Here are some links to help in its implementation. Any questions please contact us.
What Is the Basic Architecture for Serial Communication?
http://digital.ni.com/public.nsf/allkb/E0D95CB9249FB8CF86256C68007B1F81?OpenDocument
Can I Do 9-bit Serial Communication Instead of 7 or 8 bits?
http://digital.ni.com/public.nsf/allkb/3BDC7FF03541F772862564990057F919?OpenDocument
9-Bit Serial Writing in LabVIEW
http://digital.ni.com/public.nsf/allkb/E0D95CB9249FB8CF86256C68007B1F81?OpenDocument
Serial Communication Starting Point
http://zone.ni.com/devzone/cda/tut/p/id/4049
Serial Communication - Basic Serial Write and Read
http://zone.ni.com/devzone/cda/epd/p/id/2669
Enviar ou Receber Dados Binários / Hexadecimais Utilizando NI-VISA no LabVIEW
http://digital.ni.com/public.nsf/allkb/33C1056D66078118862577450061E683?OpenDocument
Sending and receiving serial commands using VISA
http://zone.ni.com/devzone/cda/epd/p/id/2423
Sincerely,
Mauro Vera
Applications Engineer
National Instruments

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Projeto - Reconhecimento de Voz e Comunicação Serial

Olá, estou desenvolvendo um projeto no qual devo reconhecer comandos de voz e enviar posteriormente informações através de comunicação serial.
A idéia do projeto é a seguinte :
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No entanto, não venho conseguindo reconhecer comandos de voz através de alguns VI's fornecidos pela NI, então venho pedir ajuda para procurar um caminho para começar a construir tal projeto.
Grato desde já.
Gilberto Neto
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Olá, achei bem interessante este projeto, porém tenho algumas perguntas:
Existe alguma especificação quanto ao Hardware para capturar o sinal?
Quando você diz: "Reconhecer comandos de voz como "POSIÇÃO 1, POSIÇÃO 2", você está se referindo que o conteúdo da mensagem falada é "POSIÇÃO 1,POSIÇÃO 2" ou que isso é uma mera identificação para uma mensagem diferente?
Capturar o sinal emitido pela voz é relativamente fácil,porém a identificação e interpretação desse sinal que é algo mais complexo (Relativo a segunda pergunta que eu fiz). Com as VI's da paleta (Sound), você irá apenas coletar esse sinal, porém a análise heurística para interpretação fica a cabo do desenvolvedor. Felizmente, existem algumas Library como o SAPI e outras para abreviar este processo.
Sobre a serialização deste sinal, você será basicamente "obrigado" a trabalhar com filas de tamanho fixo , pois os dados devem ser armazenados em sequência e serem despachados em blocos ANTES de serem repassados as funções VISA. Uma dica é repassar essa informação utilizando dados do tipo Digital (0,1) em vetores bidimensionais para assegurar que a mensagem seja serializada completamente (sem perder nenhum bit pelo caminho)
Você irá precisar de 3 Loops: Um para a captura dos dados, um para interpretação e arranjo e outro para envio das informações. Pesquise sobre a arquitetura QMH ou P/C. Não é necessário usar nada mais complexo neste quesito
Espero que eu tenha ajudado
"In theory, theory and practice are the same. In practice, they’re not."

String comunicação serial

Boa noite!
Estou fazendo um programa no Lab View que recebe dados via comunicação serial através de 1 câmera que busca posicionamento de 2 objetos, que um outro software tem que passar a posição de cada um dos objetos nos eixos x e y, e então os dados são passados pro Lab View. Recebi a indicação de utilizar a VI Basic Serial Write and Read, mas não faço ideia de como faço para integrar com a VI de controle (com a integração, eliminarei os 4 indicadores de entrada)
Obrigado.
Anexos:
Basic Serial Write and Read.vi ‏21 KB
robo10.vi ‏17 KB

Oi Ricardo, tudo bem?
Este VI Basic Serial Write and Read é um exemplo de comunicação serial na qual o VI primeiro envia um string de comando (por dafault está enviando o comando "*IDN?\n"), e posteriormente aguarda pela resposta do equipamento. Normalmente os dispositivos com comunicação serial funcionam dessa maneira: você primeiro faz a requisição do dado que você quer saber e o dispositivo responde de volta.
Na sua aplicação, pelo que entendi, você precisará ler esses dados constantemente. Então você deve utilizar o VI Basic Serial Write and Read como um subVI dentro do seu While Loop, passa os valores para as entradas do subVI e trabalha com os dados de saída.
Entretanto esta não é melhor solução para o caso. O ideal é você estabelecer a comunicação fora do seu loop e apenas enviar/receber os dados na estrutura de repetição, finalização a comunicação após o loop finalizar.
Não sei se fui muito claro. Qualquer dúvida é só perguntar!
Abraços,
Ricardo Ramos
Engenheiro de Vendas - Sul
National Instruments Brasil

How would I interface an instrument with a serial UART output to LabVIEW?

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Solved!
Go to Solution.

Yes, it is possible to transfer files with the serial port using LabVIEW. Files are just collections of bytes and the serial port is pretty good at shipping bytes from one PC to another. You need to connect the serial ports together with a null modem cable.
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Write to Binary File - At the destination side, this is what will store those bytes to the file you created with number 1.
Get File Size (under the Advanced File Functions sub-palette) - You need to know how big the file is so you know when you are finished.
OK, so once you are able to create files, write bytes to them, and read bytes from existing files you can move on to transferring.
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PrimeTest Automation

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cell: 516.819.9711
http://www.aleconsultants.com
[email protected]

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lmd2
Lawrence M. David Jr.
Certified LabVIEW Architect
cell: 516.819.9711
http://www.aleconsultants.com
[email protected]

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Sanjay wrote in message news:<50650000000500000063
[email protected]>...
> 1) The standard/built-in serial ports on your computer are almost
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Implementar protocolo de comunicação serial UART no LabVIEW

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