Good work, Matt.
Hmmm, only ten connect/disconnect cycles max, ouch:
, pg. 11
Good thing I'm not planning to install/remove this much.
To simplify the Ethernet connection, I've ordered a RJ-45 Ethernet Round Panel Mount Extension Cable, Adafruit 4215
, $5 from Adafruit or Mouser
, and I'll cut off the plug. (For those who prefer, naturally there's a similar product at Amazon
On the CAN connections: my understanding is the Best Practice is to have terminating resistors at either end of the physical bus, and that intermediate CAN devices should pass through the lines. I'm reading that any stub connections should be kept short, and that they have the potential to reflect the signal. Does anyone know if the OVMS incorporates termination? I'm assuming it's not needed, but then again I don't know a lot.
I was going to chop up a spare serial cable from days gone by, but the first two I pulled out of the bin didn't have all wires through, and then I saw, "The two CAN connections should each be twisted as pair
," and realized I'd have to run wire anyway, so gave up on chopping a cable up for this. In a previous life I used to repair computer monitors and terminals, and a common failure was when people shoved their CRT monitor away from them and the signal cable, which often exited the rear of the monitor horizontal, would be forced to a 90* bend, eventually breaking one of the signal pins. I say this to note that I'm certain that I do have a couple of DB9 (DE9) backshells in my stock, but those bins are not only in storage, they're tied face-to-face to prevent the sliding drawers from increasing entropy, and it's literally not worth $5 for me to untie/retie them right now . . . so, I thought I'd add one to the Mouser order I'm compiling. Wow, the metal backshells have gotten expensive (metal is all I'll use, too many stripped or warped plastic shells in my past). Mouser TE Conn. 571-5748676-1
, $9. Ouch. Part of living a while is you get to see prices move.
The actual DE9 connector, Mouser Amphenol DE09S064TLF
with female sockets and easy-to-assemble solder cups, $0.67 ea.
The OVMS I purchased is supplied without a SIM card (or data plan), so signed up with Hologram.io
and added a form factor 4FF-compliant Hologram.io SIM card to my Mouser order, SIM-E-TRI-GL
, $4. Once I get the SIM, I can register it with Hologram.io and it'll become active (I hope; I've never done this before, everyone's new at things once).