Hi Guys,

How do I interpret this statement?
"Serial two wire protocol with 1MHz serial clock" or "Serial digital communication interface with 1MHz clock"

I am trying to figure out whether it is RS232 standard or some other protocol for transmission. We are trying to make this transmission wireless, so looking at wireless RF modules that can replace the wire. But. this is all the info I get from the manual. I am trying to reverse engineer this product specs. Any help will be greatly appreciated. And also, some explanation on the 1MhZ clock concept helps. Thanks!

Please let me know if you need more info.

V

 

It's more than likley not RS232C standard, that requires -12 to +12 voltage swings for the high and low values (inverted)
If it's a 1mhz clock it's not going to be RS232C compliant either, it's baud rates don't go that high Id on't believe, more details on the specific devices/modules you're talking about would be helpful as the information you've provided so far doesn't really explain much.

 

It could be simple bit-banging. You can easily do it at 1Mhz.

http://en.wikipedia.org/wiki/Bit-banging

 

It's probably not rs232. That usually requires at least 3 wires (Tx,Rx, and Gnd). If I remember correctly rs485 is 2 wire communications... But I'm not sure about the clock signal...It may be proprietary. It's been a while since I've dealt with serial communications. Exactly what are you looking at?

 

It's definitely not rs232. That requires at least 3 wires (Tx,Rx, and Gnd).

I wouldn't necessarily discount it on that fact alone, a lot of people don't count the ground wire (for example, Dallas' 1-Wire protocol uses 1 wire plus ground in parasitic mode, or two wires plus ground in power mode).

 

Thank you all so much for replying.

The product is definitely proprietary. It is a GE ECG CAM-14 acquisition module. The signals are digitized and sent to a computer serially. The protocol; That's what I am trying to figure.

V

 

I wouldn't necessarily discount it on that fact alone, a lot of people don't count the ground wire (for example, Dallas' 1-Wire protocol uses 1 wire plus ground in parasitic mode, or two wires plus ground in power mode).

I suppose you are correct. Will edit previous post. Thanks.
My apologies. Apparently, alcohol has negative effects on the brain.

Forgive me. I haven't dealt with serial protocols in years.

I did a quick wikipedia search just now and found this:

"A minimal "3-wire" RS-232 connection consisting only of transmit data, receive data, and ground, is commonly used when the full facilities of RS-232 are not required. Even a two-wire connection (data and ground) can be used if the data flow is one way (for example, a digital postal scale that periodically sends a weight reading, or a GPS receiver that periodically sends position, if no configuration via RS-232 is necessary). When only hardware flow control is required in addition to two-way data, the RTS and CTS lines are added in a 5-wire version."


To have a clock signal, I would think that 1 wire would be your clock and 1 would be your Signal.....

To vijaybala85: What type of computer? Like a PC?

 

How about USB? Sounds kinda close from what I'm reading, and a lot more common nowdays.

 

I recently bought a Logic analyser, it can automatically decode several different protocols (i2c for example is clocked, and many people do not call it i2c because of licensing issues)
You select the protocol you think it might be seeing, and the software tells you what it thinks it is saying.
Could be worth a shot. Probably ~$140 for you to find out though (although I think the one which I got had a money back guarantee)

 

@c_omalley2002 The signal is sent to a CAM-USB interface with the computer. The pictures can be found on CardioSoft service manual. The software on the computer displays the ECG.

@coldpenguin I will look into it. Maybe our lab may already have one.

PLease refer attachment for info on module. Thanks!

V

 

Well, it seems to me that it may be simpler to send the USB signal coming from the interface module wirelessly. I know that cables unlimited makes such a device. See: http://www.cablesunlimited.com/products/Prod_Individual3.aspx?groupcode=I4098

That may be an easier route.

Also, I found this on wikipedia. A little more info on Wireless USB