Add the 8 pin Holteks to your long list :) HT48R002 etc On 7 December 2015 at 13:41, Bob Blick wrote: > On Mon, Dec 7, 2015, at 10:35 AM, Byron Jeff wrote: > > > Bob, > > > > My thought process is trying to track down the chip is a fools errand > > just > > because there are so many chips that fit the description. > > > > Is it possible to do a black box approach? Essentially there are only 6 > > pins to decode. Figure out which are inputs and outputs. Then use a log= ic > > analyzer to grab the functional operation of the device. > > > > At that point figure out if a PIC can mimic that operation. If so, then > > it > > really doesn't matter what the original chip was since its functionalit= y > > was captured. > > > > I hope I didn't miss some obvious flaw to this approach. > > > > BAJ > > Hi Byron, > > I pretty much figured out what it's doing. One pin sends pulses to the > LED, another monitors the phototransistor, another drives the motor. The > discretes are for buffering and the phototransistor amp. I'm not sure > what the comparator chip does, perhaps they don't trust the > microcontroller's brownout detector. > > What really caught my interest is why there are no markings on the chip. > It seems very strange. The operation is so simple there wouldn't be any > reason to try to obscure the part number. > > Best regards, Bob > > -- > http://www.fastmail.com - Faster than the air-speed velocity of an > unladen european swallow > > -- > http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive > View/change your membership options at > http://mailman.mit.edu/mailman/listinfo/piclist > --=20 http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .