That is entirely dependent on your cabling. Different cables have different capacitance per unit of length. It all comes down to segmenting and staying within that 400pF limit. Quick googling reveals an average figure of about 16pF / foot for cat5e cable.

For the system you are describing, you ...

Wow, that is a serious network. To be quite honest, this is not going to be an easy task. I2C was never really designed for that large of a network. After all it is named Inter-Integrated-Circuit bus (hence I2C). It was really only designed to be used on a single PCB or perhaps between multiple PCBs ...

Well I have good news and bad news. The good news is that yes the MX was designed to read our temperature probes and control fans. The bad news is that it has been discontinued.

Many of our other displays do have a 1-wire temperature probe input, but as of right now, none will be able to control a ...

First off, we have no intention or plans to kill off the 19264-1U series any time soon. It was released relatively recently and is rapidly becoming one of our most popular displays.

Assuming the inside of the case was positively pressured with filtered air, the cracks around the keypad would only ...

It's been a very long road. We've first been trying to resolve how to release the specs. Several things inside the company have changed how closed we want the specification to be. In the end we have decided to provide it as a free for all specification. The document will be rough, but I will post a ...

Well we have a wide range to chose from. One of our simpler designs that you can start with would be our MOS series. It communicates easily with virtually any processor via RS232 serial at TTL levels, something that PICs do very well. You can get it in a variety of sizes, 2x16, 2x20 and 4x20 are our ...

This has recently been brought to our attention through another customer. The 240x64 displays we provide have been equipped with the negative voltage generation circuit, and output on pin 20. The datasheets will be updated to reflect this in the new year.

All of the displays you have mentioned are 2x20 LCDs, the only difference will be the colours. Each comes with 3 independent fan controllers and 4 ports for temperature sensors. The 4x20 displays in the MX series come with 4 fan controllers and 6 ports for temperature probes.

The software they come ...

By the looks of it everything is correct. Nothing is glaringly wrong about your code. The first thing I might be able to suggest is putting some delay between the commands. it's a long shot, and it *shouldn't* be the case since there is a 192 byte buffer, but maybe some bytes are getting dropped ...

Unfortunately we don't manufacture the PCB that the VFD is mounted to. It is provided to us as a standard part. To change that part would not be possible without substantial NRE fees.

After looking at the mechanical drawing and a physical display, I will bring the issue with the group that takes ...

Looks like a VK204-24-USB to me :wink: . I don't think any differences between the documentation and the physical display will get in your way, but if you have any specific questions, fire away.

The red filter on the VFD is for altering the colour. The VFD is more of a greenish colour when there is ...

The documentation is ready to be released, however we have one last problem that is hanging up the release process: Licensing. To be blunt, we have had our products ripped off in the past, and as you can imagine we felt quite burned.

This time around, we have developed a very flexible and powerful ...

cipher_nemo,

I haven't seen a DC fan that can't be PWM controlled. It's just a matter of frequency. Get it well over 20KHz and you won't have any possibility of a human hearing it. Of course there are a few other tricks to help too, but I wouldn't want to give away all of our secrets

No, you're not hearing things. Our previous motor controller did use pulse control, however it did it at a much slower rate. The result is that there are artifacts within the audible range. On some fans, you really couldn't hear it. On others, you definitely could.

If we do go pulse control on ...

This one is up in the air still. If it is controlled by pulse, it will be up in the 30+KHz range to keep it WELL outside the audible range, and if someone is inclined to put a light on there, outside the visual range. Overall, pulse is much simpler to design, and far more flexible, but we will NOT ...