Pop quiz hot shot

Electrons are a flowin ;D

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Pin 7 on the Accel isnā€™t routed which is used to set the i2c address.

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solder blobs works. And donā€™t they have default addresses?

Iā€™d like to see your skills solder blobbing a QFN :whistle:

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Alas @ Bill is very much still the legend and correct about pin 7, and sadly it appears there isnā€™t a default address hence the need to tie it to VDD or GND.

So poosā€¦

And as Dave mentioned about solder blobsā€¦hahahahahahahaha not!..as you can see not all QFNā€™s are equal. Both QFNā€™s in the image are 0.5mm pitch with the RS485 IC have exposed pads on the sides as well as under so with a bit of Solder Fu and child sized fingers and a microscope you might get away with it but as you can(not) see the Accel only has pads on the underside of the package and not on the sides.

datasheet time:

To select/exploit the I2C interface, the CS line must be tied high (i.e. connected to Vdd_IO).

and

The slave address (SAD) associated to the LIS3DSH is 00111xxb where the xx bits are modified by the SEL/SDO pin in order to modify the device address. If the SEL pin is connected to the voltage supply, the address is 0011101b, otherwise the address is 0011110b if the SEL pin is connected to ground.

Did you scan I2C for both addys, just in case it worked? Are you setting CS in code?

@ Brett - indeed I RTFM before and afterā€¦seems I was lacking caffeine and the heinous pressure of client expectations lead to the loss of a postal address. And yes CS is tied correctlyā€¦

Frustration thing is that part of the design was CTRL-C and CTRL-Vā€™d from another working design but somehow the missing GND got lost in translationā€¦

grounded in translation. Thereā€™s a movie in that I reckon

@ Justin - [quote] the heinous pressure of client expectations [/quote]

ā€¦as beads of sweat appear on his forehead, dripping down, salt stinging the eyesā€¦

So are these boards going into production anytime ? or just a one off like all the previous ones ?

@ Designer - More than likelyā€¦

Also most other creations have gone into limited production, you just need to ask as I have been too busy with other mundane choirs to put them online.

But in saying thatā€¦things are afootā€¦wondrous silicon based thingsā€¦and websitesā€¦andā€¦ :wink:

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