Help indentifying this board - Page 1
Forum section: electronics / general

author: fabgar
author_rank: Contributor
timestamp: March 09, 2014, 12:45:31 pm
content: Hi, can anyone help me identify this board please ? I'd love to be able to get it to work, or get some communication going. I've been told to look for anything related to HVAC, airco/heating/furnace control ...I can find the following information on the board- There is a ARM STM32F103r8t6 MCU on it(http://www.st.com/web/catalog/mmc/FM...N1565/PF164488)- it has a USB port- on the bottom of the PCB there's a label:EMB7310 R1- on the top of the PCB there's a sticker saying:EMB 7210#722922336492118 4711There's a reset button and two buttons labeled 'A' and 'Z'. There are also LEDs near the wiring connector labeled again ... 'A' and 'Z' and three more labeled 'B' 'S' 'A' which for some people might mean something.I've searched for these clues but was unable to find anything useful.It looks like a controller/relays board, it has some relays that can switch 250v/16A, and one that can switch 14V 40/30A. Some wire connectors and two fuses. (one automotive blade fuse and a glass tube) Would be interesting to find out what kind of board this is exactly. Since it has a USB port, might be interesting to play around with it.can anyone help me figure out what kinda board this is ?thanks

author: fabgar
author_rank: Contributor
timestamp: March 17, 2014, 04:04:42 pm
content: anyone some idea ... ?

author: TerraHertz
author_rank: Super Contributor
timestamp: March 18, 2014, 04:44:33 am
content: Frustrating, isn't it?Looks like some proprietary controller board, perhaps for aircon systems. Good luck getting schematics.I feel your pain. I have six of the boards pictured below, but no useful info. They are aircon system controllers, and the CPU is a MC68HC908GP32CFB. By Motorola, now Freescale (much in the news atm.)Datasheet:http://www.alldatasheet.com/datasheet-pdf/pdf/82873/MOTOROLA/MC68HC908GP32CFB.htmlSeems like a nice CPU.I could trace the board to get a schematic, but will only do it if I ever have a need to use the boards. Not to mention finding a compiler and loader.

author: brabus
author_rank: Frequent Contributor
timestamp: March 18, 2014, 10:46:24 pm
content: I followed the design of a board like those, and I can tell you: even inside the company there was so few information transferral, that any documentation regarding the design probably lies into a random folder in someone's laptop.Small company, almost unknown, a few thousand pieces... So, I really see few possibilities to obtain useful infos, or even just schematics.Did you try to write directly to "Carrier-APAC"? Maybe, if the reader is kind enough, you will have some help.On the other hand, this kind of board is pretty easy to reverse-engineer, and regarding the uC, just wire manually a JTAG port, give supply, and try to talk with it.If my eyes do not deceive me, I see a classic 3x2 socket footprint on the first board, a nice RESET button and a few LEDs, so it's worth trying.I would not even try to disassemble the firmware which lies inside those uC, that probably are not even protected.In any case, as said by TerraHertz, I would hardly find a real use for this kind of board, it's too big for a nice and small automation project, and maybe too customized to easily interface sensors and actuators.It may be easier to just scrap them, desolder useful components (nice relays!) and design something new from scratch, what do you think?

author: Tinkerer
author_rank: Frequent Contributor
timestamp: March 19, 2014, 12:13:29 am
content: Yea, its a control board for air/heat like you were told to look under. Beyond that I have no idea.Had a mov blow on a Honeywell board for our heating. Was drawing out a schematic for it.(it was replaced, cost like $200 to do so, turns out that particular board has a high failure rate) The schematic for the board is basically not something you can find because Honeywell wont give out that info, so I suppose the same might be true for whatever board that is from whatever company.

author: ajb
author_rank: Super Contributor
timestamp: March 19, 2014, 03:18:53 am
content: Quote from: brabus on March 18, 2014, 10:46:24 pmAlthough if you are able to read out the program memory, you may find some informative text strings tucked away. Further reverse engineering is unlikely to be very useful to turning the board to your own purposes, though, unless that purpose is learning how to reverse engineer someone else's firmware.If you really want to use the board as is, your time is probably better spent reverse engineering the hardware--otherwise just harvest whatever components you like as has been suggested.

author: NiHaoMike
author_rank: Super Contributor
timestamp: March 19, 2014, 03:35:22 am
content: It's a strange one. There's an ARM processor on board to suggest some very sophisticated control, but only two or three power outputs and a bunch of I/Os. The relay terminals don't seem to have much clearance to the ground plane, so they're most likely switching 24V. There's no conformal coating, so it's definitely designed for an air handler or some other indoor device.I would guess the I/Os are for temperature/humidity sensors and maybe some other kinds of sensors. Most likely a serial bus (CAN or RS485) as well. The two relay outputs look like they might operate a damper, one to open and one to close. Therefore, my best guess is a fresh air ventilation control, since it's surprisingly non trivial to decide how much fresh air and how much recirculated air to use in order to maximize efficiency while satisfying air quality requirements. (The simple approach of checking only temperature actually causes poor efficiency in humid climates, as the A/C would then get loaded down dehumidifying the outdoor air.)

author: fabgar
author_rank: Contributor
timestamp: March 21, 2014, 12:36:04 pm
content: Thanks a lot for your input guys, really appreciate it !I (perhaps naively) thought it was going to be a bit easier; get a virtual com port driver from STMicroelectronics, plug it in and communicate directly with the MCUBut that didn't work.do these output leds/button labels 'a' , 'z' and 'b' 's' 'a' mean anything to anyone, in the context of an HVAC system ? People who work in this sector must know what they stand for (could be in German, since the board is manufactured there.)

author: Chipguy
author_rank: Unknown
timestamp: March 21, 2014, 10:52:51 pm
content: I have seen something similar.This looks like a chimney control.It is clearly a german Design. There are markings on the top right "BS" which mean "Bestückungsseite" = Part's side.The sticker "Einkalanlig" means "Single channel"The "A" and "Z" are manual controlls "AUF" and "ZU" which means "OPEN" and "CLOSE".My a chimney control: Since there is the automotive fuse in there it runs on something like 12-24VThis is mandatory for chimney/vent controls so they can set the hatch to its standby state even when the power is gone.

author: fabgar
author_rank: Contributor
timestamp: March 22, 2014, 12:41:08 pm
content: thanks Chipguy !that explains a lot ... I can now narrow down my search

author: Chipguy
author_rank: Unknown
timestamp: March 22, 2014, 05:06:10 pm
content: I found "something else" or maybe where it is from.These lasers also have a fume extractor system (one for both types).The model numbers match, but I am not sure if that is the right lead.They claim that the system can be used with fume disposal as well as with circular air filtering.http://www.videojet.ch/ch/homepage/products/laser-marking-systems/videojet-7210-7310.htmlhttp://www.videojet.ch/ch/homepage/products/laser-marking-systems/laser-fume-extraction-systems-and-filters.html

author: fabgar
author_rank: Contributor
timestamp: March 24, 2014, 11:36:19 am
content: mm, dunno about those lasers... didn't get far with them, or that fume extractor. Thanx for the tip though.I get the best results when searching for "furnace control board" I tried searching for this in German, but based on the results I must be translating it to literallyWhat's the technical jargon translation for this ?