E-mount electronic protocol reverse engineering

https://www.youtube.com/watch?v=R_In4C-jsyI

https://www.youtube.com/watch?v=2sM3TctTJBQ

https://www.youtube.com/watch?v=j1_O2dGkk3s

Entropy512 wrote: Hank - I believe that was similar to an approach someone had for a REALLY long EF extension tube that they 3D printed. It had some ideas for going forward whenever I get back around to this. The lens side of almost any mount interface is going to be easier - your strategy would probably work well for most mounts. The problem is the camera side (or for an adapter, the "adapter to lens" side), since those have spring contacts. At least one person has succeeded with pogo pins (the EF megatube guy), although it was really finicky. AHA - found it - https://sherlock-photography.github.io/canon-extension-tube/ I just haven't had the time to alter this basic idea to my needs.

Nice reference. I 3D-print a lot of adapters including the flange parts, and most of my designs print in as few pieces as possible without supports, but that does make the design harder than using an assembly with commercial flanges. I definitely think wire-wrap is better for the connections than straight soldering, but the E breakout extension tube I'm using now was just soldered.

My brother has had some luck using pogo pins on various other projects, and that's certainly a more "official" possibility for the lens end of the adapter, but I was thinking it might suffice to have a bit of springiness to the mounting of the part that holds the contacts. It's quite easy to 3D-print a leaf spring. Anyway, no time to explore this space right now....

BTW, all of this stuff is really finicky. The tolerances needed for alignment of the pins with full contact area are just barely within what a cheap extrusion-based 3D printer can do (gaps between pins are just barely printable without having to drill 'em out like the adapter you reference). Last month, I bought a Mars 2 Pro resin printer in the hopes that I can get about 5X tighter global part tolerances, but I haven't even done a test print with it yet. Pogo pins should pair better with resin prints.

Just to be really technical about this, even pogo pins are not really the officially correct mechanism for a set of contacts that rotate into position -- although they are used by many cameras. It should really be spring-loaded ball contacts... which are even harder to deal with.

Edited by profhankd - 22 January 2021 at 13:56

Entropy512 wrote: I wish someone who was more mechanically inclined than most of us seem to be would create an "adapter breakout" device - EF to E mechanically, but breaking out both EF and E to 0.1" headers.

I have a different breakout connected right now (a modified extension tube), but my first attempt was a 3D-printed flange with holes for brads. Basically, you put the brads in locking them in place with heat from a soldering iron, sand down the outside surface to make smooth contacts, and then wire-wrap to connect to them on the inside. Thick copper wire would probably work even better than brads.

I've been too busy to do anything more with that; I had 3 papers at Electronic Imaging 2021 on other things and have been working on open source plans for a 2.6GP large-format scanning camera I built. However, the adapter pin design does allow 3D-printing arbitrary adapters with electrical contacts, and you also can embed electronics parts in the 3D printed design by printing traceless PC-board-like mounts and wire-wrapping to them.

Realistically, this probably will not advance much until this Summer... but by then I expect to have my lab at the University of Kentucky at least partially operating again and getting students involved....

Hi,bostwickenator,thanks so much .
R2A30440 is strongly important for decoding many details of focusing Commands from camera body to A036 , as well as lots of Focusing/Aperture status sent from A036 to camera body.
Anyother SoftWareManual of R2A3 series chips is important also,
i believe that motor controlling CMDs are almost same in R2A3 series .     

vitor , Thanks so much .
however R2A30440 Datasheet does't help unfortunately ,
because there is no description of R2A30440
controlling commands in the datasheet.

In TAMRON A036 Lens ,
Renesas chip R2A30440 is responsible for Focus motor and Aperture motor controlling,
in A036 firmware , i found lots of codes that communicate with R2A30440 ,
Could anybody share with User Manual of R2A30440 so i can decode these codes.

bostwickenator wrote: You should pull my Teensy code. It does all the negotiation stages and enters the main message loop. From there it should be pretty easy to do what you are talking about. Also I have docs for the message sequence. Just please don't start from scratch again 3 of us have gotten to roughly this point before giving up. https://github.com/LexOptical/E-Mount

I wouldn't say necessarily that anyone has given up, more like taking an extended break... This project has always been in "spurts" for me. (I've always had a bad habit of not completely finishing projects...)

Glad to see you here Hank, your posts on dpreview are always incredibly useful, and most importantly, your 3D printing skills are way beyond mine.

My lack of mechanical ability to go beyond "hacked extension tube" always limited where I could go.

I STILL have a Teensy I haven't gotten around to setting up to run Alex's code yet. I swear I'll do it one of these days.

Sorry for the slow response - when this thread activity happened I was on family vacation, and forgot about it until the Pentax adapter news reminded me of it.