Parallax is LIVESTREAMING the unboxing of the Propeller 2! https://youtu.be/01TyfRtSjkI
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in Propeller 2
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I'm frantically wondering what happened.
They unboxed it and chip soldered one to a board, but they haven't fired it up yet.
I have a bottle of bubbly waiting here for "first light". Really.
Eight years or more effort. A huge pile of money invested. And the P2 arrives in a tiny, anonymous brown cardboard box like a $1 ebay purchase from China.
Live stream dropped out.
Surely here are better PSUs / metering options there somewhere ?
Multimeters are ok, but check that 1.8V on the chip-side is still 1.8V, as many meters have voltage drops.
Better is to use a low Iq LDO, and to meter on the Vin side, where 200mV of meter drop, do not matter.
If a low drop mA meter is not easy to find, an alternative is to use eg 1Ohm series R, for 1mV/mA drop, and then a 200mV low cost meter range gives 0.1mA LSB, better meters give lower LSBs
30mA of core drain then drops 30mV, tolerable.
That 0.79v on IO pins is sounding suss.... it's about what one would expect if the TEST pin was the only GND connection, and GND itself tab was one parasitic diode elevated.
A meter between IO and PCB GND (PCB totally unpowered), should show parasitic/esd diodes, when pulling the IO negative - if the GND TAB is connected properly.
Not the real Marko?
Also diode checked from IO to GND should confirm if GND pad is connected.
1. A lot of heat was supplied to the chip when soldering the ground pad. Could this have damaged the chip?
2. Didn't Peter put series protection resistors on the I/O pins??? Might these be needed (or shorting) on Reset, Serial In and Serial Out ?
Might it be worth Fedexing a chip to Peter so he can test too? He knows the pcb and has parts.
BTW the pcbs on the picknplace will not require all parts to be placed as some are either/or options. Peter needs to comment.