Right, sorry. I missed that you meant to use the rj45 to db25 adapter. -- bkw
On Thu, Feb 25, 2021, 12:47 AM Francois Gurin <[email protected]> wrote: > On Wed, Feb 24, 2021 at 8:59 PM Brian K. White <[email protected]> wrote: > >> > if you want to use rj45 -> db25 hoods, you should check out a cable >> like https://www.amazon.com/gp/product/B078PT5N24 >> <https://www.amazon.com/gp/product/B078PT5N24> which will just plug into >> an android device with usb c port and give you a rj45 end to plug into >> > --francois >> >> Then you still have to cut off the rj45 end and solder on a db25. >> >> It also assumes the android device has a usb-c jack. >> I made an equally unsafe assumption that the android device has micro-usb. >> >> If you're assuming usb-c, you could combine the OTG cable and usb-serial >> in one with this: >> https://www.amazon.com/dp/B074VM88G1 >> Then you just need the serial cable I showed, or the two mini adapters >> in the mComm manual. >> >> I guess the advantage with the usb-c adapter is, if you have both a new >> phone and a new laptop, then they both have the same usb-c jacks, so the >> same adapter works on both without an extra OTG cable for the phone. >> > > You wouldn't cut off the rj45 adapter, you'd use an rj45-db25 hood > either pre-wired or one you custom -- wired > https://www.amazon.com/InstallerParts-Female-Modular-Adapter-Ivory/ > > Not so much these days, but it was common to have multiport serial servers > terminate in rj45 so you could either connect them directly to console > ports (with, for example, cisco devices) or wire them up to appropriate de9 > and db25 adapters. because the adapters are inexpensive, you could easily > have them terminate as straight through or null modem, and this was helpful > for servers that had very particular serial console pinouts. > > the OP mentioned using these connectors already, I have boxes of them > somewhere myself so it's a way of leveraging existing hardware. it > wouldn't be efficient to use a usb -> 9pin usb serial adapter, then a 9pin > -> rj45 cable, then an rj45 to db25 hood (but it would work!). also, the > rj45 -> db25 wired as a null modem takes up less space behind the m100 than > a usb -> serial adapter and the matching slim null modem and de9->db25 > adapter (unless you've created a custom connector). > > i linked to a usb c cable, you can get a similar cable with usb a and use > it with an otg adapter. my favorite usb serial adapter is > https://www.amazon.com/DTECH-Serial-Adapter-Supports-Windows/dp/B01AT2FTOU/ > as it has both 9pin and 25 pin availableat a right angle, but you still > need a null modem adapter > > However your cable is short, which is a different advantage I didn't > consider --- you don't want 6ft of cable between 2 devices that are going > to be close together! > > --francois > > >
