leccyflyer Posted July 31, 2023 Share Posted July 31, 2023 15 minutes ago, Nigel R said: The ST chip is actually a whole microcontroller, or CPU. This widget could be doing anything. Might be a mixer. Or a door sequencer. Or a reverser. Or a tester. Or then again, it could spell out 'sausages' using morse code if you connect an LED to one of those plugs. John Kallend on RCG has something which does exactly that. 🙂 Quote Link to comment Share on other sites More sharing options...
Mike Blandford Posted July 31, 2023 Share Posted July 31, 2023 The STM8S003F3 is a: Value line, 16-MHz STM8S 8-bit MCU, 8-Kbyte Flash memory, 128-byte data EEPROM, 10-bit ADC, 3 timers, UART, SPI, I²C so it is a processor, not just a timer. My guess is the 4 empty pads are used when programming the device. To see if the connectors are likely to be for servos, check (using a multimeter) to see if the 3 pins closest to the board are connected together, and the next row up are also connected together. Also of the 4, empty pads at the end of the board, 1 is surrounded by a lot of copper. This is a ground plane, so that pad is also ground. See if that is connected to the bottom row of pins. Mike 1 Quote Link to comment Share on other sites More sharing options...
KenC Posted July 31, 2023 Author Share Posted July 31, 2023 OK 2 more snaps to try and show details ... Quote Link to comment Share on other sites More sharing options...
KenC Posted July 31, 2023 Author Share Posted July 31, 2023 Mike my electronics test skills are I am afraid rather poor. However with a simple circuit tester I have obtained a circuit on all of the lower 3 pins ..... then holding one of the lower three, I touched each of the upper sets randomly and the needle similarly deflected ! At this point I decided to quit before I fried something . Quote Link to comment Share on other sites More sharing options...
EarlyBird Posted July 31, 2023 Share Posted July 31, 2023 55 minutes ago, Mike Blandford said: My guess is the 4 empty pads are used when programming the device. I made a mistake I should have said pin 18 not 13. Pin 18 is indeed the SWIM pin for programming the MCU and as Mike said have not been used. Could be anything then, the puzzle continues. Quote Link to comment Share on other sites More sharing options...
RottenRow Posted July 31, 2023 Share Posted July 31, 2023 The new pictures confirm that the central row of pins are all connected together and also supply the voltage regulator. You can’t do any harm by connecting a receiver output (or a servo tester if you have one) to one set of pins, and a couple of servos to the others. Just make sure that the signal wires (white or yellow) are uppermost, and black closest to the board. Then operate that channel (or the tester) and see what happens to the servos. If nothing, move the Rx / tester connection along to the next set and try again. There are only three connection possibilities really. Mike is right about the function of the four ‘unused’ pads - the square one goes to pin 18 on the uP which is for serial programming data. Brian. Quote Link to comment Share on other sites More sharing options...
KenC Posted July 31, 2023 Author Share Posted July 31, 2023 The file I have has been greatly reduced by the posting process, I can assure you more detail is possible of localised areas if it would assist . So to confirm the pins are in vertical sets with the lower horizontal set of three presumed as the ground signal , the mid three as the +ve, and the upper three presumed as the signal ? Quote Link to comment Share on other sites More sharing options...
PatMc Posted July 31, 2023 Share Posted July 31, 2023 (edited) The fact that all 3 connectors are pins means that a normal extn lead can not be used to connect either a servo tester or Rx. To me this suggests that this gismo is a stand alone device that needs it's own power input. PS is there a land extended to the centre connector signal pin ? Edited July 31, 2023 by PatMc Quote Link to comment Share on other sites More sharing options...
KenC Posted July 31, 2023 Author Share Posted July 31, 2023 Just FYI when I received this ( in a box with a magpies array of bits) there was the lead, as shown in the first pic at the start, with three , red, black, white wires and "futaba" style plugs attached to the middle three pins vertically . This I presume servo wire had a small sticker with the number six printed on it . Quote Link to comment Share on other sites More sharing options...
Phil Green Posted July 31, 2023 Share Posted July 31, 2023 Impossible to tell from what you see, its a generic processor board, its function depends entirely on the software programmed into it, and that is most probably read-protected 🙂 Quote Link to comment Share on other sites More sharing options...
Nigel R Posted July 31, 2023 Share Posted July 31, 2023 patmc, you can see from prev page that all signal pins are connected via the 47ohm resistors... middle pin track goes around top pin to the top 47ohm res. 1 Quote Link to comment Share on other sites More sharing options...
Keith Billinge Posted July 31, 2023 Share Posted July 31, 2023 Oooh it's an exciting thing! Plug your servo tester in and some servos and see if it's just a reverser or a slowy-downer or a sequencer..... Quote Link to comment Share on other sites More sharing options...
KenC Posted July 31, 2023 Author Share Posted July 31, 2023 Was trying to follow the pin paths in the last photo to see if all three sets were equal. I found that the side image lost the detail of the tracks close to the pins .... so here is a better one . If plugging my Toolkit RC M7 AC servo tester into one set , I was trying to figure if there is an input signal from receiver , and an output to servos. Quote Link to comment Share on other sites More sharing options...
leccyflyer Posted July 31, 2023 Share Posted July 31, 2023 1 hour ago, KenC said: Just FYI when I received this ( in a box with a magpies array of bits) there was the lead, as shown in the first pic at the start, with three , red, black, white wires and "futaba" style plugs attached to the middle three pins vertically . This I presume servo wire had a small sticker with the number six printed on it . Maybe it's the control circuit for one of these? https://thumbs.gfycat.com/VapidBountifulLeveret-mobile.mp4 Quote Link to comment Share on other sites More sharing options...
KenC Posted July 31, 2023 Author Share Posted July 31, 2023 (edited) 3 minutes ago, leccyflyer said: Maybe it's the control circuit for one of these? Hmmm could be as its got a number and no name ! Rather offers a hint to electro designers.... a small label on the item saying " hello I am a delay timer for retracts ... Please plug receiver into channel marked 1" . Edited July 31, 2023 by KenC cause I can ! Quote Link to comment Share on other sites More sharing options...
kevin b Posted July 31, 2023 Share Posted July 31, 2023 (edited) Looking at the age of the board and the fact that it is one input and two outputs with no controls and its size, I would say that it is a servo reverser for two ailerons. Possibly supplied with an old ARTF kit. There are two sets of similar components on the board and one set has one wired the opposite way round. Possibly current direction ? When it comes to electronics I studied under that great instructor Philip E. Stine. Edited July 31, 2023 by kevin b Quote Link to comment Share on other sites More sharing options...
RottenRow Posted July 31, 2023 Share Posted July 31, 2023 1 hour ago, KenC said: So to confirm the pins are in vertical sets with the lower horizontal set of three presumed as the ground signal , the mid three as the +ve, and the upper three presumed as the signal ? Yes that is correct. The unit will get its power from the receiver or servo tester. As you’ve since said that the separate lead was connected to the middle set of pins, I would reconnect that, connect the other end to an Rx channel or servo tester, and connect a couple of servos to the other two sets of pins. Then switch on and see what happens… Brian. Quote Link to comment Share on other sites More sharing options...
KenC Posted July 31, 2023 Author Share Posted July 31, 2023 7 minutes ago, RottenRow said: Then switch on and see what happens… It didn't work Rotten 4 Quote Link to comment Share on other sites More sharing options...
kevin b Posted July 31, 2023 Share Posted July 31, 2023 I think I have found out where it goes. 1 Quote Link to comment Share on other sites More sharing options...
KenC Posted July 31, 2023 Author Share Posted July 31, 2023 (edited) 30 minutes ago, kevin b said: Looking at the age of the board and the fact that it is one input and two outputs with no controls and its size, I would say that it is a servo reverser for two ailerons. Kevin its 2013 by the marking , and I had servo reversing on my Futaba 8UP back in the late 90's Note its the 6th Nov ...... a day earlier and I might be worried ! Edited July 31, 2023 by KenC Quote Link to comment Share on other sites More sharing options...
KenC Posted July 31, 2023 Author Share Posted July 31, 2023 (edited) Another shout out to electronics designers ... remember the days in the computer industry when sensible people would print a small triangular marker on the board just so you understood the pin settings. Edited July 31, 2023 by KenC Quote Link to comment Share on other sites More sharing options...
David perry 1 Posted July 31, 2023 Share Posted July 31, 2023 (edited) It certainly appears that the four through hole plated holes were never used so they appear to me to be a red herring. Leaves us with three vertical servo plugs. As suggested...go from rx to anyone of them and to a servo from the other two. Then play around. You might damage the device, which is unlikely, but thats about it. Oh...video it. Edited July 31, 2023 by David perry 1 Quote Link to comment Share on other sites More sharing options...
EarlyBird Posted July 31, 2023 Share Posted July 31, 2023 38 minutes ago, KenC said: Another shout out to electronics designers ... remember the days in the computer industry when sensible people would print a small triangular marker on the board just so you understood the pin settings. The dots tell us where pin 1 is Then count down that side to pin 10 and up the other side 11 to 20. Steve Quote Link to comment Share on other sites More sharing options...
Andy Stephenson Posted July 31, 2023 Share Posted July 31, 2023 The 4 unused pads on the board are for in-circuit programming of the microcontroller chip during the manufacturing process. That's why they are not exposed to the user. Quote Link to comment Share on other sites More sharing options...
KenC Posted July 31, 2023 Author Share Posted July 31, 2023 8 minutes ago, EarlyBird said: The dots tell us where pin 1 is Great info EarlyBird but what about the input and output pins ... before I would, as a simple high street guy , be willing to connect to these I would want to know which is input ( for receiver or servo test) and which are outputs . When the thing was sealed no one was prepared to make guesses because the 9 pins visible were similar and unmarked ! Quote Link to comment Share on other sites More sharing options...
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