Reprogrammed a Lily Tiny with a Tiny AVR Programmer and SOIC clip?

#1

Can someone who has done this successfully help me please?

I’ve been trying and just can’t get it to work.

I have now snapped off the second set of right hand headers on the Programmer (hard to get the jumper wires in and that weakens the bond) and am on the way to burring my second SOIC IC test clip (doesn’t clip so easily over the ATtiny chip and slips off).

Is there a secret? I am an electronics noob so it could be my technique. But women are usually less rough with things aren’t they? :slightly_smiling:

Meanwhile I’m using the Programmer to program a standalone ATtiny85 successfully but I want the physical qualities of the Lily Tiny and would love to sort this out

Here’s hoping…
Sally

#2

PS
Here’s the link to the description
https://learn.sparkfun.com/tutorials/re-programming-the-lilytiny--lilytwinkle?_ga=1.69426326.707710893.1435561981

#3

Yes, I’ve used the Tiny AVR ISP Programmer from Sparkfun to program individual ATtiny85 in 8-pin DIP, and over a six pin programming cable to a target board with an ICSP pinout. Used either the Arduino IDE or avrdude directly.

But I’ve not yet used a SOIC clip or the LilyTiny. As it has an ICSP pinout on the back, I’d be inclined to try that, with a temporary surface mount header, pogo pins or tack soldered kevlar insulated silver plated wire (aka wire wrap wire).

When you say you can’t get it to work, what happens when you try?

Can you use a multimeter in diode or resistance mode to prove the clip is working for each of the six critical pins? This can work because of the diodes built into each pin as the signal arrives on the chip. Let me know if you need detailed steps.

Is there anything soldered or attached to the pads of the LilyTiny? Attachments can interfere.

Inspect the SOIC chip pins with microscope or other magnification; are they coated with anything? A conformal coating can prevent a clip from finding the right position, and can insulate the contact.

#4

thanks for replying Quozi
I think from memory it was an avrdude error when i tried to upload code but I didnt make notes and now I can’t try your excellent debugging tips because half the headers have snapped off the programmer. I’m not sure I want to buy a third programmer if I don’t know what I’m doing wrong. I did use ribbon cable male-femaile jumper wires, rather than individual jumper wires, but the problem was poking the male side into the headers - didn’t go in easily and pushing in weakened the bond. Did you have this problem?

Anyway I’d like to try your suggestion of using the ICS pinouts on the back, but i barely understand your suggestions. If there are any references you could direct this noob to I’d be grateful - have not found anything really useful yet. Maybe I can try a pogo pin adaptor when my soldering skills are a bit more predictable :sligcry:

#5

G’day Sally,

When you say the headers have snapped off the Tiny AVR ISP Programmer, no, I’ve never seen that before. It is possibly something unusual you’re doing with the headers.

I’ve got my programmer in front of me now, and compared it with the product photographs from Sparkfun.

When you say headers, they aren’t strictly headers on my programmer; they are a pair of rows of machine pin IC sockets, in surface mount style, either side of the PDIP IC socket. They look delicate, because of how they are attached only to the top surface of the board.

This type of machine pin IC socket works best with the pins on IC packages, or with similar diameter round cross section solid core jumper wire.

I’ve sets of many different jumper wires from our sponsors, including a coloured ribbon cable. The el-cheapo jumpers end in a tinned copper bar, which has a circular cross section. The coloured ribbon jumpers end in a machine folded bar with a square cross section. I would never use these in the machine pin IC sockets, and carefully guiding one in now rings alarm bells for me; it doesn’t settle, and so the cross sectional area of contact will be quite variable.

Now, the PDIP 8-pin IC socket is a different matter. It is a through-hole mounting, soldered on both sides of the PCB. So it would require a greater breaking force. The sliding contacts in the PDIP IC socket are suitable for coloured ribbon jumpers, if you are careful not to rotate them. So you can use these instead of the machine pin IC sockets.

More to come …

I’ve looked at the ATtiny85 datasheet from Atmel, and the PDIP and SOIC packages have the same pinout.

If you have programmers with those headers broken off, don’t discard them, they might be brought back into some sort of service.

#6

An ICSP connection for the ATtiny85 only needs six signals. It doesn’t matter how the signals are electrically connected to the LilyTiny, as long as they are connected at the time you start avrdude, and the wires are sufficiently short. My preference is not to exceed 20cm, but there are ways to overcome distance if that’s a problem.

On the Tiny AVR ISP Programmer, each of the six signals are available from four attachment points each;

  • six of the machine pin IC sockets you’ve been using, (two are unused),
  • six of the sliding contacts in the PDIP IC socket, (two are unused),
  • the six holes all in a line at the very end of the board,
  • the six holes in two rows of three in the middle of the board.

When one of the connection points is broken, or not the right sort of connector, one just uses another more appropriate point.

You can figure out the pin ordering with a piece of paper, pencil, and a multimeter set to conductive beeper mode. That’s the mode where the meter beeps when you touch the probes together.

Sorry, I don’t have a reference to learning how to do this, as it is a skill I’ve learned gradually over many years.

The Sparkfun tutorial you linked to really does assume you’ll use the machine pin IC socket pins either side of the PDIP 8-pin IC socket. It would complicate their tutorial to give all the other ways it could be done.

#7

Oh Quozi, I AM SO HAPPY!
It has now worked, at least once.

I understand now that I was literally pushing square pegs into the round holes of the machine pin IC sockets (I called them headers). Thats why I was damaging them with the wrong jumper wires and it also wouldn’t have helped them work.

I went on to try your suggestion of putting the same “pegs” into the sliding contacts in the programmer’s PDIP IC socket.

No success at first - its is rather tricky to position the SOIC IC Test Clip but after almost being ready to give up, I did at least once get it to work.

Have to get back to work now but am very pleased to be able to continue with my project now and very grateful for your help. Thank you Little Bird Community!

#8

Good to hear.

Every connector has a limited life, as the metals get worn. Expect the PDIP IC socket to wear out eventually. Do look for any encapsulant or clear varnish on the SOIC IC, and if there is any you’ll have to clean it off the test clip.

You might be interested in http://littlebirdelectronics.com.au/products/eclip-programming-fixture which would use pogo pins touching the underside of the LilyTiny.

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