Help identifying component

[Snoo]

Hello, Im trying to find out what is this chip: its on a small Fujifilm IR remote shutter control for digital cameras. The idea was to re-program the code for Pentax (or substitute the chip if necessary?). On the chip i can read FR220-1 483 839102... in the marker in the corner i can distinguish an MX but not sure if could be a manufacturer logo or just a marking with no meaning for me.

 

[pjmelect]

The MX is MagnaChip I think, https://www.magnachip.com/product/glance.php
However I think the part you are looking for is a custom micro of some sort.

 

[Snoo]

the link doesnt open for some reason but anyhow i thought the logo of magnachip was an MC and MX was Macronix, again its in the marker at the corner of the chip so might not be a logo at all or it could be an asian character that looks like mx.
if i search for fr220-1 the only thing i pull up are MOSFETs... Is there any way to find the pins i need poking around this thing?

 

[betwixt]

The black capacitor is across the ground and supply pin, the yellow resonator is across the oscillator pins and the black transistors are between the output pin and the LED. I would doubt it is possible to reprogram the device though, these kinds of IC are mask programmed with specific device address and command bits at the factory. It would however be easy to duplicate it's functionality with a small microcontroller as long as you know the pulse sequence needed by the Pentax camera and have space to build the new circuit. It is very unlikely you would find something pin compatible.

Brian.

 

[Snoo]

The black capacitor is across the ground and supply pin, the yellow resonator is across the oscillator pins and the black transistors are between the output pin and the LED. I would doubt it is possible to reprogram the device though, these kinds of IC are mask programmed with specific device address and command bits at the factory. It would however be easy to duplicate it's functionality with a small microcontroller as long as you know the pulse sequence needed by the Pentax camera and have space to build the new circuit. It is very unlikely you would find something pin compatible.

Brian.

It seemed way too easy to have opened it up and found something recognizable :sad: I dont know if there are some tricks to figure out the pins other than what is visible following the tracks of the circuit... dont have much experience with that...
There is room on the board to move things around, might not look pretty at the end but as long as it works... The thing is that i will have to look through the junk i have to find something with a low profile, or it wont fit back in its case... its a 1$ surplus item and i would have preferred not have to take it all apart and rebuild it...
In the meantime im reading a bunch of unuseful stuff on fuji though :roll:... for example this is a pre-2007 thing since it has the old fujifilm logo

Edit: As it turns out the F in the first line might not be a letter F given the way its printed, maybe a logo maybe not and what i thought was an MX its infact japanese, meaning Kawamata, and not sure if its a logo at all... so...boh:???:

 

[betwixt]

Sorry to bear bad news but I don't think you will get far. The way these things work is: a low power detector looks for voltage on the input pin (connected to one side of the big circular pad) which is present only when the conductive carbon dot on the rubber key mat bridges the two sides. This 'wakes' the IC and starts the 455KHz oscillator running. The 455KHz is divided to produce a 'carrier' signal, typically dividing by 12 to make 37.9KHz. the carrier is then pulsed in a very specific pattern, rather like morse code and then sent to the LED. The LED stays on for a short period, maybe 50mS then sends the flashes in two parts. The first series of flashes is a product code and afterwards the second set of flashes is a command code. Both are specific to the device it is to control, the device code must match the one expected in the camera and the command code must tell it what operation it is to perform. Each different model has it's own product code (aka it's address), this is how it knows not to respond to the wrong remote control unit. The coding is built in at the factory and can't be changed. With such a specific task to perform, you wont find a generic replacement, you have to start from scratch. It isn't difficult if you use a general purpose microcontroller but you do have to write your own software to produce the right flash sequence. Your first problem would be find out the flash sequence you need and the speed at which the pulses are sent, not easy unless you have a working unit to copy from.

Brian.

 

[Snoo]

Thanks Brian, This one is for a Fujifilm camera, one shutter button, just that, i know which code is using... also have the code for Pentax that should have replaced it, so that part is taken care of... This one i might replace it, all the looking around on the net kept going back to Renesas, some of their 4bit ones, but who knows how old it even was back then when they used it which already has to be more than 6 years ago... have a couple of TI uC somewhere i could use eventually, all the other components and the enclosure and battery are perfectly usable...