New Project wp34s micro usb flash cable revisited

[MarkHaysHarris777]

(02-04-2015 11:09 AM)brouhaha Wrote:  (1) It's possible I'm confused about what you're doing, but doesn't that result in a calculator that has a micro-USB connector that isn't electrically USB? that doesn't seem like a good thing to me.

(2) I'm also unclear on the motivation; USB-to-serial chips are fairly inexpensive. I'm fine with putting one in each calculator.

(1) That is correct. It is RS232 (sort-of) made available on the micro usb connector which eliminates the need to use the pogo pads for update, provides 3.4v power for the unit, provides a rock solid connection in a tiny space, and serves the specific purpose of updating a functional wp34s.

(2) I'm ok with mounting the FTDI PL2303HX in the wp34s... and I may do that on one of my units... but I'm still going to start with the FTDI connector. One of the things I don't like about Harold's board is the paradigm of mounting the micro jack out-the-side, and the need to modify the case to get the board and jack into place due to size. The FTDI plug can be disassembled so that only the board needs to be mounted (small drop of epoxy, the board is tiny) and then fine bell wiring runs to the pcb AND to the female micro jack (which instead of being mounted through the side, which is ugly, it is mounted in the back plate under the battery cover; when not in use you don't even see it).

I'm still mulling it around on the drawing board...


cheers