trinket breakdown

[mike808]

Hi all,

I have a couple of trinkets (5V and 3.3V) and my projects work great on them. My next step was to try an build a trinket myself on a breadboard and have my simple USB project run on there. Here is what I have setup (see image below). Those wires which are connected to the ATtiny85 chip are connected to this cable (http://www.adafruit.com/products/954) with wire colors in the file comment. I have uploaded my hex file using the USBTiny programmer (http://www.adafruit.com/products/46) to program my ATtiny85 chip. (note bigger chip, ATtiny2313 is not used in this setup, but I have it on the board)

The issue: I have VUSB implemented in my program (like I do on the trinket, which works). However, when I connect the USB TTL cable to my computer, I do see the cable as a USB device

Code: Select all

067b:2303 Prolific Technology, Inc. USB-Serial Controller

but I do not see my USB device. Clearly, I must be missing "stuff" that the trinket has that my breadboard setup does not, but I am not sure what. Can you please advise?

[AnneBarela]

A bit beyond Trinket....

But, I think VUSB is supposed to emulate the USB directly (see Trinket schematic). You may need three resistors to get things right but I don't think the TTL to USB is what VUSB is thinking when it communicates. You could just program the tiny85 for standard TTL serial "console" and use your cable and save alot of space that the VUSB code uses but that would be less of a Trinket clone.

[mrburnette]

I wrote an article on building your own Trinket:
http://www.hackster.io/rayburne/chachka ... ny85-clone

After you are successful in getting your clone working, you may want to try:
http://www.hackster.io/rayburne/trinket ... e-exorcism


Ray

[mike808]

thanks ray! interesting posts.

i was able to get mine to work on the breadboard like this. don't have a bootloader running, so need to program the chip via usbtiny each time i tweak it. however, i managed to get my vusb config setup and working which is what i was after.