Jolt.js, first tests

[espruino-discuss]

Posted at 2024-07-11 by @yerpj

Hi,

Just wanted to share my happiness: I just received a brand new Jolt.js ! (see attachment). I must say it is a very cute tiny development board and I really expect doing great things with it.
Thank you @gfwilliams for always putting a lot of effort in both firmware and hardware!

I don't have Qwiic peripherals yet but now that I have a great controller I will definitely buy some.

I just wanted to know a bit more about power outputs. Is there a way to use them as dry-contact outputs (as a Normally Open Relay would do) ? I looked for the schematic but it seems not to be (already) online.

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Attachments:

• PXL_20240711_095229309.jpg

[espruino-discuss]

Posted at 2024-07-12 by @gfwilliams

Hi! Great - I'm glad you're liking it! I think you might be the first buyer!

For anyone interested - I'm on holiday next week but when I get back I'll be adding a 'plus' kit to the shop that has a few more connectors, a screwdriver and battery (it's still an identical board to this), but at that point I'll start trying to advertise Jolt.js a bit more!

Is there a way to use them as dry-contact outputs (as a Normally Open Relay would do) ?

I'm not entirely sure I get what you mean, but I don't think so, no.

The motor driver IC is https://www.ti.com/lit/ds/symlink/drv8847.pdf

The 8 outputs on the terminal block can be pulled up/down or left open (but not connected together like relay contacts). Even when they're open circuit, there are still clamp diodes to the power rails.

There are 2x FET outputs on the Qwiic connectors which at least are only clamped to 0v, but I think that's unlikely to be what you need either and I wouldn't advise using them for anything too heavy duty.

If you really want a truly isolated switch-style output, I think your best bet is just to attach a small relay to the terminal block, and then you can switch whatever you want (including mains).

I looked for the schematic

Ahh, sorry - just added to https://github.com/espruino/EspruinoBoard/tree/master/Jolt.js

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Posted at 2024-07-12 by @allObjects

Obviously missed the announcement... great move to add these power drivers onto the board, and a nice name for the product. As a plug-and-play, it is a leap-up from wire-and-play. Had to order a Jolt.js right awa, incl. a backup.

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Posted at 2024-07-29 by @yerpj

Thank you for your quick answer, your explanations and the schematics!

Looks like with FETs on Qwiic interface we can have a dry-contact output (even if it is not isolated from the circuit).

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Posted at 2024-09-27 by @gfwilliams

Just a note for others that the 'Bundle' kit with extra bits is now available in the shop: https://shop.espruino.com/joltjs-bundle