Probably not permanently missing, this time.
Sometime within the last couple of weeks, I saw a breakout board for a not-FTDI USB UART. I think I classified it as "will want again someday, but not real soon", and accordingly packed it in one of the "lab stuff for later" boxes.
The chip in question, if memory serves, was from Microchip; I bought the board to evaluate the chip for a project for which it turned out to be unsuitable (something to do with modem-control signals, if memory serves).
Well! Now I need a logic-level (not RS-232) UART. I have several options handy... all of which are based on FTDI chips.
Which wouldn't be a problem, except that the gadget I'm working on involves a Lattice CPLD, and the eval board for same, and the programming interface on the board is built around, yes, an FTDI USB UART, used in bit-banging mode.
So, when I want to reprogram the CPLD, I need to make sure the ftdi_sio driver is inactive, or the CPLD-programming program won't be able to talk to the hardware.
Which means that none of the FTDI UARTs connected to this computer will be working as UARTs.
I wish Lattice had at least programmed the chip with a different VID/PID, so the driver wouldn't recognize it by default.
Oh, well. I guess I use one of the dongles I have on hand, and just accept that I won't be able to reprogram the CPLD and test communication at the same time. And maybe I should order another not-FTDI logic-level UART dongle.
Update: Rummaging around Spark Fun turns up a couple of options (whereof one or the other probably lurks in some already-packed-up box of goodies). But, that wouldn't be here before sometime-next-week, which is not convenient.
OK, so look for pl2303 on Amazon. Bingo! Various boards with no RS-232 level shifters. A little further digging turns up a cable assembly with 3.3V I/O, which is what I need at the moment, and also a three-pack of non-cable boards (with chips from three different vendors, all not-FTDI) for not a lot of bucks. All with Prime (and free next-day delivery with a qualifying $35 order, but I don't feel like padding the order this time, and besides I won't have time to work on this project before Monday afternoon anyway).
One cable dongle and one three-pack assortment of non-cable dongles ordered. Just under $20, for Monday delivery.
Some aspects of the modern world are good.
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