Hi Guys
I think I'm looking for something that probably doesn't exist outside of industry, but maybe you can prove me wrong?
I want to program some smd ATTiny85s but don't have room on the planned pcb for programming pins. Is there an 8 pin socket capable of holding 8 pin smd components like the ATTiny, and where would it be available from?
Bernie
This?
Thats exactly the sort of thing Fungus. Thanks for pointing me in the right direction, I can now search UK sites using the right nomenclature!
Bernie
He he, for a tightwad person careful with his budget, some of those solutions are worth stealing adapting! I especially like the "hold with a bulldog clip and hope it doesn't move" approach XD
Bernie
If you use a socket in your final design, you are wasting space. If you use a socket in the programmer only and then solder the device to your board, you can't change the program. Why not use a miniature 6-pin ICSP connector instead? Perhaps the 6-pin version of this: http://uk.farnell.com/molex/501331-0607/header-1-0mm-pico-clasp-6way/dp/1835980.
I'm not using a socket in the final design, the ATTiny85 is soldered direct to the pcb. I'm not too worried about not being able to re-program after assembly as the processor function isn't going to change, I just wanted a way of programming the SMD ATTinys from a Uno, without using my breadboard, before assembly .
I've finally decided to use a custom etched board with the smd ic footprint on it with tracks leading out to pins that'll plug direct into the socket of my programmer shield (http://www.flytron.com/open-source-hardwares/162-tinyshield-all-in-one-avr-programmer-shield-for-arduino.html). I'll glue a small piece of (probably) thin ply with a hole cut in it over the ic pads, so the chip is located properly and then clamp it in place with a plastic clamp. I'll post a piccy if it all works ok.
Cheap n' cheerful - like me!
Bernie
For my next project I've been thinking of leaving some pads near the edge of the PCB so the board can be plugged into a connector like the one below if the chip ever needs to be reprogrammed...
Is there something like this for for SMD 328P chips?
some kind of 'clip/holder' that adapts to a breadboard for quick flashing of those 328P TQFP chips?
I am having the same 'problem' to deal with.. there will NOT be enough room/space on the PCB to add in any ICSP headers/holes for flashing bootloader later on.. (having enough of a problem adding in any sort of holes/pads for serial programming/sketch uploading as it is!)
some kind of contraption with pogo pins... to set/secure the chip and the pins.. and connect to leads for flashing bootloader (just going to use my old Arduino 2009 for flashing bootloader like I do on all other custom boards)
anything out there you guys know about or have seen?
thanks! 
xl97:
I am having the same 'problem' to deal with.. there will NOT be enough room/space on the PCB to add in any ICSP headers/holes for flashing bootloader later on.. (having enough of a problem adding in any sort of holes/pads for serial programming/sketch uploading as it is!)
If all you need to program is the bootloader, then just flash it and set the fuses once, before you solder the chip in place.
Do you need the serial port for anything other than uploading the program? If not, ditch the serial port and bootloader, and put an ICSP header in some of the space you save.
hi dc42-
I guess Im not understanding ...lol
I 'do need the bootloader on...
I am 'asking' about a clip/socket/holder that can do the SMD 328P QTFP chips.. so I can flash it BEFORE soldering it into place.
I 'do' need the serial 'port' (RX/TX/DTR/3.3v/GND) pads..... Im 'trying' to find a place for them on my PCB.. (making another post on that as we speak/type) so that after the fact/assembly... if the sketch needs to be changed or edited a bit.. it can be. (instead of an assembled PCB that cant be updated)
so your saying.. dont even use the Arduino bootloader? just flash sketch to chip directly.. (give more space on the chip too)?
I have never done that before.. and a bit out of my comfort zone I guess too.
right now just looking for something that can HOLD the SMD 328P chip.. and have some pogos/pads (whatever) on certain pins to flash a bootloader to..
thanks!
I guess you could solder something like this to a custom board and use pogo pins as you planned?
Bernie
xl97:
so your saying.. dont even use the Arduino bootloader? just flash sketch to chip directly.. (give more space on the chip too)?
Yes, include a standard 6-pin ICSP header on your board (or a smaller 6-pin connector if you wish) and flash to the chip directly, after the board has been assembled. This is the standard way of programming custom designs. It also reduces the startup time (since the chip doesn't have to check whether you are trying to upload a new program to it) and frees up pins 0 and 1. See Prototyping small embedded projects with Arduino | David Crocker's Solutions blog for more.
thanks for the link.. I'll have to look into those (maybe some locally?) lol..
I cant see the bottom.. not sure how I can solder any leads to it? but as far as holding/securing the 328PU TQFP chip.. it looks like a winner.!
@dc42-
hmmmm... pretty attractive having not only the space.. but D0/D1 available for use now..
along with faster boot times too...
to be clear there is NO ROOM for ANY sort of header.. (none).. the most I can hope for would be some via/through holes for this.. in an in-line fashion, using .05" spaced/sized holes.. and thats pushing it.. more likely I'll need to use pads (not through hole/vias).. VERY tightly together... and some sort of custom made pogo pin/jTag connector to hold in place while I flash/upload...
my current challenge"
the whole PCB is less than 1"...(and a custom shape!)
no parts on top of PCB outside of main MCU
uSD socket on bottom of board...have fun fitting in all the components for the rest of the circuit..hahaha.
I actually posted some pics of the project here (if interested in visually seeing the challenge)
http://arduino.cc/forum/index.php/topic,138646.0.html
thanks!
I can't see any pics in that thread.
There is a link to a USB tester but that seems to have plenty of space.
Rob
yikes..
copy/paste error..
(sorry) lol
http://arduino.cc/forum/index.php/topic,138646.0.html
also -
I dont think that link will work will it? (ebay socket) PLCC != TQFP.. does it?
Is there such a thing for 32 pin TQFP sockets?
thanks
PLCC != TQFP.. does it?
Nope.
I think you can get sockets for just about every type of package but that can be VERY expensive.
It looks to me though that there's plenty of room for some pads for pogo pins or for one of the smaller versions of these
Rob
Here is a socket... \
http://www.emulation.com/pdf/skt109.pdf
Beyond cost what else was the issue, Code not mature enough yet for pre programming the processors?
These have been common for 10+ years...
Albeit not cheap then... Before China...
Not too expensive now.
Come to think about it. The job wouldn't be at all difficult to fabricate one. Not at All nut it would take an accurate hole and some accurate pcb tracks to be laid out
around the inside edge of a square hole cutout for the IC, drop the ic into the hole to contact the part solder tabs and apply some pressure to make sure each pin was tight on the pad below it and use a pressure plate to hold it... Easy to do... for one sized package though, not really very "Universal".
What I found that was Clever was the 8 pin SO-8 programming "Clip" made from a PCI card connector... That WAS ingenious and clever too...
Bob
include a standard 6-pin ICSP header on your board
In general, you won't even need to do that. Since the 4 pins used by ISP are already likely to connect to other parts of your circuit board, you might find it trivial to make sure that there is a via or connector to each of those signals, where you could use some sort of "programming fixture" for programming the chip.
For example, if the Arduino did not have the ISP connector, you could still connect an ISP programmer via the Digital pins 11, 12, and 13, and the RESET pin on the bottom connector.