Trying to get at that electronic interface? Well, there’s no point in trying any harder to search the Internet for documentation on that interface. No, that is private knowledge only found in the heads of camera repairpeople who have been working on that technology at the time. So, that problem aside, let’s look toward reverse engineering the interface.
20180318/Google reverse engineer electronic communication interface logic level 5 v
Oh, this is really helpful, but it only scratches the surface, with an emphasis on modern devices.
20180318/http://resources.infosecinstitute.com/reverse-engineering-of-embedded-devices/
Not so helpful.
20180318/=https://www.element14.com/community/thread/37817/l/reverse-engineering-old-serial-devices-and-cloning-with-arduino?displayFullThread=true
Okay, so what did I find from doing my own analysis. Put the battery inside the camera and use a volt meter to analyze the 10 contacts inside the film bay. I find that all voltages are in the 4 V - 5 V range. Good, so we know that this interface is somewhat similar to RS-232/RS-422 serial interfaces, at least in terms of voltage/logic levels. Also, we observe a similar number of pins: 10 pins is quite similar top the 9 pin plus ground shield serial connectors. But, the fact that I observe a range of voltages means that these are likely analog connections.
What’s more, this is really weird. Even after I remove the battery from the camera, some pin pairs still have a significant voltage reading for quite some time. Well, there must be some pins that are meant to measure the proportional voltage inside the flash capacitor, I presume. Either that, or this is simply an artifact of the general functioning of the camera logic where the LCD screen logic still operates for a few seconds even after the battery has been removed.