FTDI/Serial or USB?

[Samuel235]

Good afternoon,

I'm currently split between the idea of having FTDI header pins or a USB Mini-B connector along with its counterpart, the ft232rl IC, on my new module: Homini Complete Room Sensor Module.

Would there be any advantage in its capabilities of either one i choose apart from physical layout? Obviously the USB and IC is taking up more footprint room compared to the FTDI header pins.

[TheoL]

I'm no expert. But if you don't want to us the USB as power supply (is that possible?) I'd go for FDTI. Save space and hardware. And if you're node supports OTA, you're probably never gonna connect the USB of FDTI after the initial software is loaded anyway.

[Samuel235]

@TheoL, I'm very tempted to get this module working with OTA sketch updates, then I would definitely go for the FTDI option simply just for debugging reasons. I'm also thinking FTDI anyway because of the smaller footprint, i was just wondering how many people actually have a FTDI - USB programmer. I didn't know if it was just a handful of us that use FTDI or pretty much the whole community.

[TheoL]

@Samuel235 I think that most of us, have at least one ProMini. So I expect that we all have an FDTI programmer available. Besides that an FDTI programmer isn't that expensive. It might be good to calculate what the return on investment is. How many USB and IC's can you buy for one FDTI programmer?

[Samuel235]

@TheoL, it wasn't so much just the cost factor of putting either onto the board, it was about the convenience of usb compared to the FTDI for the user.

[DavidZH]

The main question should (in my humble opinion) be: how often do you plan to update your sensor while it's in use? USB is very convenient, no doubt. But FTDI is almost just as easy when you prepare an adapter with a single connector that you slide on and program away....
Even if you plan to make more than one sensor the debugging will be longest with the first. (Hopefully!!!)

Either way, good luck on the build!

[GertSanders]

I was thinking that an USB connector could be handy to power the board. The three other pins on that connector could be TX, RX and DTR. But that is with a FTDI to USB connector conversion and with still using the FTDI interface. Only advantage: needs less space on the PCB.
Then again, you could switch to an mcu with built in USB like @tbowmo does in his gateway.

[Samuel235]

With me wanting to add an additional power port to power this module via a wall socket while programming (this may pull more current than allowed on the programmers). I'm tempted to use the USB option, that way i can have the two USB sockets on-board, have one feed the module power and gnd and then the other for the data lines.... that way the board would be receiving the power and current needed from the wall socket, and the data connections to the programmer....

[TheoL]

I have attache a dupont cable to my FDTI programmer and wrap electric tape around the dupont connectors. For me connecting an FDTI to a board takes a minute. Of which I spent 40 seconds to be sure the cable is connected the right way.

Adding USB to a board makes it harder to mount in a casing. At least that's my experience.

[DavidZH]

Actually, I use the FTDI connector on my outdoor weather sensor to power it from the solar/Li-Ion charger board. Used angled headers to keep the height down. I'll try to post a picture asap.