I tried vision code 254 which gave the same error rate as before (although it was a different error, 4001 this time)... then I switcehd to 255 which almost never gives an error except for a mis-picked component.
However, the parts are now very inaccurately placed on the board. There is a lot of space in the pockets of the embossed tape, so I think it's not really able to center correctly on vision mode 255, and those boards will require manual movement of most of the placements to get them just right.
Anyone have any ideas on how to get this working? There are other PLCC (such as PLCC-32 and PLCC-44) components defined with vision code 102 and 105. 102 says it's for PLCC and 105 isn't in my manual, but I suspect it's the same but for a newer version of the firmware.
I was originally using 105 but I tried switching to 102 prior to just turning it off with 255. I tried adding 1mm to the pick-up tolerance, as well as setting the lead tolerance to 60%. I also tried setting the X and Y dimension tolerances to 0.6mm with no luck (they were originally 0.2mm as per manufactuers specs).
Any other suggestions? One thing I noticed is when I went to set the CCD level, I manually pick a part and place it on the nozzle, then when I hit start to capture the image, and press F->2, I have to scroll down to the bottom to see the image... and the outline of the legs isn't very clear. The legs are sort of blurred together. I had tried lowering the CCD offset in the part definition to -50, but it still looked bad. Could this be the source of the problem? When I captured the image manually, then went into F->2 (to show the image as binary bits), the whole screen was just cluttered with random blocks. It didn't resemble a part at all.
Vision & centering works perfectly with all the other parts - including SOIC's, 0805, 0603, 1206, SOT23-5 and tons more - I maybe 1 part in several hundred... so the vision system seems to be working fine. I just can't get it to like the PLCC LED's.
The only thing about the PLCC's I was thinking may be an issue is their housing is white plastic, whereas most chips are black (although the bottom of an 0805 is white too). Any suggestions? Try lowering the CCD level more?
Thanks in advance for any advice.
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