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The Serial TTL connector we deserve

kohlschuetter.github.io

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Re: The Serial TTL connector we deserve

#5

Post by dazhbog »

I cannot count how many PCBs I did with various quick connect ideas to have a fast way to debug..

- Chop a PCI connector and have edge fingers on the PCB

- Skedd connectors

- Micro usb with a toggle switch or solder blob to switch between SWD/UART or USB

- Low profile usb-c and have D+/- as normal, and RX/TX over the accessory pins (like audio)

- Pogo pin clips

- GH1.25 connectors

- Tag-connect meh

- If thickness of pcb allows, your PCB can plug directly into a USB-A port (Thicc pcb) or if its too thin, it can plug into a male usb-c connector from a charger cable(might bend some pins though)

etc. etc.

So just like the author, anything but Dupont connectors ;)

Re: The Serial TTL connector we deserve

#6

Post by eqvinox »

The only things with a chance at succeeding in this space are putting USB-serial directly on the board + USB-C, or alternatively bluetooth classic RFCOMM profile. (The latter is a very long shot.)

Apart from that, this doesn't even touch upon the various voltage levels for logic-level serial ports, or the question of whether to Vref or not to Vref. (Or RTS/CTS.)

Re: The Serial TTL connector we deserve

#8

Post by foresto »

FTDI (the company practically synonymous with TTL serial adapters) uses 3.5mm tip-ring-sleeve connectors for this. In other words, a common headphone jack.

I added one to my single-board computer enclosure, following FTDI's wiring. Now I can easily connect whenever I need to use the serial console, and a standard 3.5mm audio extension cable will let me reach across the room without moving my main computer. Replacement parts, if I ever need them, are cheap and easy to find.

Here's the pinout:

https://www.ftdichip.com/Support/Documents/DataSheets/Cables...

Re: The Serial TTL connector we deserve

#9

Post by eqvinox »

foresto wrote: post #8

FTDI (the company practically synonymous with TTL serial adapters) uses 3.5mm tip-ring-sleeve connectors for this. In other words, a common headphone jack. I added one to my single-board computer enclosure, following FTDI's wiring. Now I can easily connect whenever I need to use the serial console, and a standard 3.5mm audio extension cable will let me reach across the room without moving my main computer. Replacemen…

That really sucks for hotplugging since TRS connectors sliding in basically make random connections before seating properly.

Granted, you shouldn't hotplug TTL serial, but everyone™ does it anyway. (In some situations you're even forced to, to avoid reverse powering something.)

Re: The Serial TTL connector we deserve

#10

Post by foresto »

eqvinox wrote: post #9
foresto wrote: post #8

FTDI (the company practically synonymous with TTL serial adapters) uses 3.5mm tip-ring-sleeve connectors for this. In other words, a common headphone jack. I added one to my single-board computer enclosure, following FTDI's wiring. Now I can easily connect whenever I need to use the serial console, and a standard 3.5mm audio extension cable will let me reach across the room without moving my main computer. Replacemen…

That really sucks for hotplugging since TRS connectors sliding in basically make random connections before seating properly. Granted, you shouldn't hotplug TTL serial, but everyone™ does it anyway. (In some situations you're even forced to, to avoid reverse powering something.)

They're not random connections; they're predictable. I'm not worried about Tx briefly touching Rx or ground in these devices.
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