Is it possible to find serial output if you know all parts on a PCB?

[jimmydanny]

Hi! New guy here, going here because, well, it is electronics, and no matter where you use electronics, the same principles are at work.

So, I got a keyboard matrix... well, I don't have it myself, and I can probably never get hold of one myself, so I can't use a sniffer/analyzer to find what I need.

But I mostly all components in images and name except some smaller capacitors.

It is a keyboard matrix with 24 buttons, a keyboard matrix to parallel controller, D Flip-Flops, an UART and a RS485 chip to get the TTL over to RS485 specs.

If I gave you guys all my images, the names of the MCs, even the datasheets, is there any way you (we?) could find out what the serial outgoing com looks like, or at least narrow it down to the point I can use some hours, instead of months, in HyperTerminal with a USB-RS485?

If you deem this project at all possible, I will post all the images and other info I got on this.

Cheers for any input!

Jim, Norway

 

[(*steve*)]

Well, since there's a UART there, that would be a great place to start

 

[jimmydanny]

To all this, I will add that I understand maybe the VERY basics of integrated circuits and low voltage electronics.

I can use software far better than average, and overclocking is not something that I am afraid to do.

 

[jimmydanny]

Forgot to actually finish. I know my software, but I am unsure on electronics.

The Keyboard matrix controller is a KR9601, the UART is a AY310150, and the 485/422 is SN 75179BP.

Due to time restraint I can't get you the crystal, voltage regulator and flip flops and other stuff right now (images), so hold on if you need that as well

 

[jimmydanny]

Here is a link to the album with the images from the original PCB: http://imgur.com/a/g4AlH

The pictures are taken with a DSLR and are rather large, so I don't wanna piss someone with a 64k connection off or something!

EDIT: Well, here is one picture just so you see without clicking the link. For the skeptical, never heard anything bad about imgur!

 

[davenn]

Due to time restraint I can't get you the crystal, voltage regulator and flip flops and other stuff right now (images), so hold on if you need that as well

They are all easily readable on your photo

As Steve said, you know what the UART is so google that part number and see if you can get a datasheet for it
then you may be able to do some tracing to the I/O connection in the upper centre


Dave

 

[jimmydanny]

I have read the data sheet, but sadly, as i said, i know software and mechanical stuff

I dont understand what i get from it, so i am unsure what i can do with that.

But i do know a lot of the connectors go to the keyboard encoder just above.

What i want to do, is to find out what key 1 and 2 would give in output.

I should add that this is for bowling, so there are ten buttons plus set and cancel per side, so 24 buttons/keys.

You press any combo of 1-10 keys and when you press set it sends the command (i would guess, but it could be that it sends one and one key for each pin then sends the set command?).

 

[jimmydanny]

I might have started in the heavy end of this, ill admit. But then again, if i can find the bits around the data bits, and the data bits for one key plus set, i can possibly get somewere by being bored at work for weeks to come

 

[GPG]

You need to find out if NB1, NB2, NP, TSB and EPS of the UART are connected to Gnd or 5V This will give you the number of data bits, parity, stop bits.

 

[Martaine2005]

Is that tool (top left) in the photo part of your SMD rework station?

Martin

 

[jimmydanny]

This is another alley that is the only one in Norway afaik that has ever hd these.

Not for sale new anywhere, and used is as hard.

 

[jimmydanny]

The Vcc going into the KR9601 seems to be going to the mentioned NBs, NP, TSB and EPS on the UART.

 

[GPG]

That corresponds to 8 data, 2 stop, no parity. You will have to trace the clock circuitry to find speed or measure the frequency of the clock pin.

 

[jimmydanny]

Would it be wrong to assume that the recieving end would have the same speed? Because that i can probably find with analyzing Equipment, either analyzer software or osciloscope.

Can i find what the data bits will look like from this then? I know what each key will give from the keyboard encoder, not sure how the flip flops are connected in all this, but for my use it is probably not important anyways.

 

[GPG]

Would it be wrong to assume that the recieving end would have the same speed?

Pretty much necessary. The 2 stop bits will cover a small discrepancy. The bit rate is 1/16 clock.

 

[jimmydanny]

So I can find what the other end sends out, and this will most likely be the same speed as this end sends... That is the easy bit in any case then.

My issue now is finding what the keyboard actually gives out, and how it is put together when sent in combinations, I bet this is where the flip-flops comes into the picture, as you can send any combination, and it is sent as one command (if it is split up in the serial com is another case, but the input from the bowler is one input when he press the "Set" button).

You have no idea what it would mean if I (with I I mean we, even more correctly you, as my knowledge of this is minimal at best lol) could do this. Worst case I can at any time connect a computer and tell the pinsetter to do X, and it does it for me.

Right now I have a rather stone age solution to this, which is kinda working, but hard to work: 10 pins, and the table that holds these pins (the table is the thing that puts the pins down, and picks them up to remove deadwood in between shot 1 and 2) has pin holders with sensors/switches in them. So when all 10 are sensed, it can set them down. If I then cut the power to the solenoids letting these pins be set down, I can set down what I want.
The problem with this is that I have to do it after first ball, because it doesn't drop down all pins into the table until after it has checked what is left, removed the deadwood, and put the rest of the pins down again.

I am working with a continuation of this idea, if I (you) can't crack the serial comm code here, which goes on using a pre-existing switch that senses if the table is up or down. I can use this to disable power to 10 relays (in place of the 10 switches I use now), so my setting function isn't working except when the table is NOT up. The reason for this, and the reason I can't disable the solenoids when the table is up is that the solenoids also let the pins fall down as they press a lever so the pins can fall down. And since these machines are so technologic, the machine will stop and give error codes on missing pins.

I can't find the image of my setup, but it is basically 10 switches on a plexi-plate that is set up like the pins are. For my 2nd revision to work, I would need these switches to be connected to 10 relays, SPST, and the power to all these switches has to go through the table position sensor with a SPDT relay. But we are easily talking $100 per machine, and even though we got just 6 pinsetters, $600 is a lot.. 6 pinsetters, it is a reason we only got 6, there is no market for more.

 

[GPG]

How about a video clip of the system/procedure unmodified/modified I know bugger all about bowling machinery

 

[jimmydanny]

If you mean the general operation of the pinsetter, there you go. This is a newer revision, but the mechanics is the same.

The electronics is different tho, as it uses a single switch to detect standing pins and pins in the pin holder, where ours uses cross wired switches, so it cancels out the 12v signal for either a standing pin or a pin in the pin holder, and shorts the circuit to let the current go through if there is no pin or two pins detected.

Else there is the electronics and comms that we dont use, as they are some weird type of hdlc that requires a interface pcb to make use of.. this one i cant get hold of at all, costs $700 so it is not happening. If i could translate the comms on the fly in an easy way, i would not need to decipher the keyboard serial comm at all.

 

[jimmydanny]

Here is the hdlc pcb, which translates the hdlc/sdlc of unknown standard over rs485 (bitbus?) to some other unknown standard over rs485 that most scoring systems understand oob, probably something rather standard.

 

[GPG]

costs $700 so it is not happening.

So i guess a trip to Norway is out of the question