Olimex Support Forum

Microcontrollers => MSP430 => Topic started by: daekhan on July 20, 2022, 09:20:58 AM

Title: MOD EKG waveform
Post by: daekhan on July 20, 2022, 09:20:58 AM
Hi.
I buy MOD EKG Board.
And I tested and connect between mod-ekg and PC, run scope.exe.
HeartRate count value is displayed LCD.

But, GUI waveform is strange form. not PQRST form.

The ECG waveform picture in olimex application doc, is diffenent my GUI.

Why??

Cloud you check this?

Thanks.
Title: Re: MOD EKG waveform
Post by: LubOlimex on July 20, 2022, 12:57:19 PM
What USB-UART adapter do you use? Did you follow all advice from "Connecting MOD-EKG to PC via MOD-USB-RS232 board.pdf"? Did you select the proper COM port (how is the USB-UART adapter listed)?
Title: Re: MOD EKG waveform
Post by: daekhan on July 22, 2022, 04:06:25 AM
Thanks for replay.

Yes. I read "Connecting MOD-EKG to PC via MOD-USB-RS232 board.pdf"
MOD-USB-RS232 board is not sell anymore(mouse.com or and so on)

So, I bought BB-CH340T Board of olimex and another USB  to ttl Conveter.

Case 1. Using BB-CH340T
- modify COM1 in control pannel.
- connect and displayed slowly changed waveform. But, not EKG Waveform.


Case 2. Using another USB TO TTL Converter
- modify COM1 in control pannel.
- connect and displayed fast changed waveform. But, not EKG Waveform.

For good EKG Waveform, Should I buy "MOD-USB-RS232 board"??
If so, How to buy "MOD-USB-RS232 board"?

Thanks.
Title: Re: MOD EKG waveform
Post by: LubOlimex on July 22, 2022, 08:56:40 AM
Can you show me how the waveform looks like?
Title: Re: MOD EKG waveform
Post by: daekhan on July 25, 2022, 04:15:15 AM
Yes..

https://blog.naver.com/PostView.naver?blogId=daecan72&Redirect=View&logNo=222827705455&categoryNo=1&isAfterWrite=true&isMrblogPost=false&isHappyBeanLeverage=true&contentLength=2992&isWeeklyDiaryPopupEnabled=false

Thanks.


Title: Re: MOD EKG waveform
Post by: LubOlimex on July 25, 2022, 10:58:00 AM
Hmm, it actually shows that it reads alright (scale is proper, there is different data coming in, it is not missing or a straight line or something), but the overall reading is not what you would expect from EKG.... Do you hold the metal pads with your thumbs and index fingers tightly on top and bottom of metal pads? Maybe the readings get distorted by something else - by source of power or USB or some noisy piece of electronics nearby? Maybe the power supply is shaky as described on MOD-EKG's product page in the FAQ at the bottom?
Title: Re: MOD EKG waveform
Post by: daekhan on July 26, 2022, 08:24:52 AM
I replay your question.

Do you hold the metal pads with your thumbs and index fingers tightly on top and bottom of metal pads?
==> yes

Maybe the readings get distorted by something else - by source of power or USB or some noisy piece of electronics nearby?
==> not used usb poower.

Maybe the power supply is shaky as described on MOD-EKG's product page in the FAQ at the bottom?
==> yes. i use coin battery for TEST1.
==> after reading in the FAQ, i use JTAG(MSP430-JTAG-ISO-MK2) external power for TEST2
==> Test1 and Teset2 is all same not EKG waveform.

How can i get right EKG waveform?


I have another question.
When i tested as follow.
- use Coin batter at the back of MOD-EKG.
- disconnect exteranl serial port.
- disconnect jtag connector.

after then, i contact my thumb and finger. In the LCD Arrow blink and realtime change hearrate.
My hearrate is 71.

But, after i connect serial port(to coverter USB), I conntact my thumb and finger, arrow not blinkg and
not change heratrate number realtime.
When use External power in Jtag(MSP430-JTAG-ISO-MK2), all same thing.

Why not blinking in exteranl connect serial or jtag ??

Thanks a lot.