Hi all, i just discovered node-red 3 weeks ago and i developed a dashboard to send query to a modbus server with success so i am happy. Now i need to interact with a MCP4725 to send variable voltage to control a device. I found only a node-red ncd for the MCP but it is an old library and doesn't wo…

Welcome to the forum! node-red-contrib-i2c will probably work. You need to look at the datasheet for the MCP4725, to understand what you need to send as commands. Unless someone here has already used the MCP4725 and can offer help, you will have to work this out yourself. There may also be an alte…

Thank you. Anyone else? Experienced this chip ?

Hi all After many research and after installing a I2C decoder on my computer, i can say that this node works only with a simple device. i understand now this node. You set the bus number for the device so in my case : 1 You set the Bus Address of the device so for the MCP4725 0x60 so 96 decimal …

Hi, I publish a mcp4728 and mcp4725 node and library on next days. Please wait.

<a name="p-406196-hi-all-because-i-love-to-find-and-with-the-help-of-chatgpt-here-is-a-function-code-in-node-red-to-calculate-the-12-bits-of-the-output-voltage-for-a-channel-described-in-the-i2c-out-note-that-i-use-vref-vdd-so-the-gain-is-ignored-to-calculate-the-12-bits-you-need-to-keep-the-first-4-bits-of-the-first-byte-with-a-value-depending-of-the-vref-parameter-and-gain-you-want-in-my-case-i-only-need-vrefvdd-so-the-datagram-is-0x60address-0x58-command-for-the-channel-a-and-vref0-pd1-and-pd2-0-gxx-ignored-and-the-12-bits-with-the-second-bytes-to-determine-the-output-voltage-here-is-the-function-to-write-1" class="anchor" href="#p-406196-hi-all-because-i-love-to-find-and-with-the-help-of-chatgpt-here-is-a-function-code-in-node-red-to-calculate-the-12-bits-of-the-output-voltage-for-a-channel-described-in-the-i2c-out-note-that-i-use-vref-vdd-so-the-gain-is-ignored-to-calculate-the-12-bits-you-need-to-keep-the-first-4-bits-of-the-first-byte-with-a-value-depending-of-the-vref-parameter-and-gain-you-want-in-my-case-i-only-need-vrefvdd-so-the-datagram-is-0x60address-0x58-command-for-the-channel-a-and-vref0-pd1-and-pd2-0-gxx-ignored-and-the-12-bits-with-the-second-bytes-to-determine-the-output-voltage-here-is-the-function-to-write-1" aria-label="Heading link"> Hi all Because i love to find and with the help of chatgpt, here is a function code in node red to calculate the 12 bits of the output voltage for a channel described in the I2C out. Note that i use VREF= VDD so the gain is ignored. To calculate the 12 bits you need to keep the first 4 bits of the …

[image] @iiot2k/node-red-mcp4725 Node-Red node for mcp4725 digital to analog converter [image] @iiot2k/node-red-mcp4728 Node-Red node for mcp4728 digital to analog converter

Thank you for your node. Why do you use the multiwrite command instead of the single write command ?

I think you mean the modes in mcp4728. The single write mode writes also to eeprom. This makes the writes slow and often write to eeprom reduce the lifetime of eeprom.

That makes sense. I noticed in the single write command that output voltage was not as expected . I don't understand why. did you test in this mode ?

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MCP4725 and I2C node-red-contrib-i2c

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Francois 28 March 2024 16:49 6

Okay. Thank you

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MCP4725 and I2C node-red-contrib-i2c

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