After using T3.2's for a couple of years without a failure, I have been having all manner of problems migrating my (several) projects to the T3.6.
I've now purchased 6 T3.6's, and over the last 8 months have not yet managed to get a single project ported over, and have spent countless hours chasing silly problems, including ILI9341 displays failing while connected to the 3.6. I'm starting to question whether the hassle is too much.
The latest is that I have 3 new T3.6's that will not boot-up on power on - even running blink.ino. It's driving me crazy! Here's the situation:
All are mounted on Tindie 64-pin breakout boards with headers so they can be swapped in and out. All 3 work well when powered via USB. In my lab prototypes, however, they are powered through an on-board 7805 regulator from a HP lab supply set at +9.0v. The voltage measured at the T3.6 Vin pin is 5.06v. There is an on-board on-off switch and a voltage reversal protection diode (1N4005) before the regulator. All measured voltages make sense.
If I power up (with the on-board switch on) by turning on the HP power supply none of the Teensies will boot up. If I turn the PS on first, and then turn on the on-board switch they will "usually" - but not always - boot. It's independent of the code loaded - as I said above it happens with the humble "blink" sketch as well as my large app codes.
If they fail to start I can kick them into action by grounding the RESET pad after which they perform fine until the next power on.
What gives? The only common factor is the HP power supply. I'm wondering if the T3.6 boot cycle is edge triggered and the HP rise-time is just too slow? I have yet to try a RC delay network to hold RESET low briefly on power up, but I shouldn't have to go that far. BTW, I have played with the values of the input/output electrolytics around the 7805 regulator with no effect.
I've now purchased 6 T3.6's, and over the last 8 months have not yet managed to get a single project ported over, and have spent countless hours chasing silly problems, including ILI9341 displays failing while connected to the 3.6. I'm starting to question whether the hassle is too much.
The latest is that I have 3 new T3.6's that will not boot-up on power on - even running blink.ino. It's driving me crazy! Here's the situation:
All are mounted on Tindie 64-pin breakout boards with headers so they can be swapped in and out. All 3 work well when powered via USB. In my lab prototypes, however, they are powered through an on-board 7805 regulator from a HP lab supply set at +9.0v. The voltage measured at the T3.6 Vin pin is 5.06v. There is an on-board on-off switch and a voltage reversal protection diode (1N4005) before the regulator. All measured voltages make sense.
If I power up (with the on-board switch on) by turning on the HP power supply none of the Teensies will boot up. If I turn the PS on first, and then turn on the on-board switch they will "usually" - but not always - boot. It's independent of the code loaded - as I said above it happens with the humble "blink" sketch as well as my large app codes.
If they fail to start I can kick them into action by grounding the RESET pad after which they perform fine until the next power on.
What gives? The only common factor is the HP power supply. I'm wondering if the T3.6 boot cycle is edge triggered and the HP rise-time is just too slow? I have yet to try a RC delay network to hold RESET low briefly on power up, but I shouldn't have to go that far. BTW, I have played with the values of the input/output electrolytics around the 7805 regulator with no effect.
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