Trinket Pro and Bluefruit EZ-link

[flounder]

I had great success a couple days ago using the EZ-link to program a Menta. I notice that in the description of the Trinket Pro, you don't mention the EZ-link programmer, or have it in the "people who bought this also bought..." section. I just got an order placed tonight, so I haven't tried it yet with the Trinket Pro, but my latest design critically depends on this working...
joe

[adafruit_support_mike]

It should work, but you'll need to connect the EZ-Link to the FTDI pins on the end nearest the Pro Trinket's reset button.

The connections should be the same as for an Uno, with TX<=>RX connections both ways, 5v, GND, and a capacitor between the DTR line and RST.

You might not be able to program the Pro Trinket through the EZ-Link if you're taking power from a USB cable though. The bootloader emulates a USB connection the same way a Trinket does, and the code that decides whether to use USB emulation is tied to the code that decides whether to program as a Trinket or using Optiboot. You might need to supply 5v from a non-USB source to make EZ-Link programming work.

[flounder]

Thanks. I'm a bit confused by the reference to "the FTDI pins on the end nearest ... the reset button" because as I look at the photo , there appears to be only one set of FTDI pins, on the side nearest the reset button. I expect I would have the same problem as I did with the Menta, which is that the FTDI connector is a voltage source, but the EZ-Link is just a voltage sink.

I am also a bit curious why all the dimensions are given in inches, and not mm (learn.adafruit.com/introducting-pro-trinket/downloads).. (Note that "introducting" is as spelled in the link).
joe

[adafruit_support_mike]

"On the end closest to the reset button" was meant as a dependent clause. If you already know where the FTDI pins are, it doesn't give you any new information.

The dimensions are in inches because that's still the dominant standard in PCB fabrication. Pin header and DIP pins are on 0.1" centers, SOIC pins are on 0.05" centers, and TSSOP pins are on 0.025" centers. The standard layout grid is 0.05" for parts and 0.025" for traces. 0.012" and 0.010" are the most common values for trace width and spacing. If you convert all that to two-decimal-place metric, you end up with small offsets between your grid and most of the packages in the libraries.

Thanks for mentioning the typo. I'll pass that along to the folks who manage the Learning System.

[flounder]

Followup: I got my Trinket Pro. I plugged the BlueFruit EZ-Link into it. I ran a jumper from the +5 to the Bus pin, which provided the required voltage to the EZ-Link. It works perfectly. Note that I now have an Arduino R3 true equivalent, in that I can write to Serial and see my debugging output. This is just about the perfect solution. I don't need to provide a USB connection to program it in situ, or a reset button to put in in programming mode. Note that the IDE tries to recompile the sketch, even if it has not been changed! This compilation takes longer than ten seconds. This was one of my many problems trying to use the "Classic" Trinket. But all those problems are gone. I continued doing development on this platform without any difficulty, and as soon as I can reprint the case with the new mounting footprint, the project will be finished. Oh, and I dropped the reset button and USB connector from the case, so the only connectors are for power and the sensor. Makes the whole thing less cluttered.

[adafruit_support_mike]

Nice. Glad to hear it's working for you!