SHIELD-EKG-EMG + Arduino Uno Best Configuration

[ajebulon91]

Greetings all!

I have read many postings and threads about how to make this SHIELD-EKG-EMG works, especially for Arduino Uno which is one of the most widely used. I found so many users proposing different configuration compared to the default configuration from Olimex.

1. Olimex basic guide: https://www.olimex.com/Products/Duino/Shields/SHIELD-EKG-EMG/resources/SHIELD-EKG-EMG.pdf
H/W Config:
REF_E – closed
3.3V/5V – 5V position
D4/D9 – D9 position
ANI_SEL – 1 position (channel)
Electrode Placement:
Right arm - Exact position unspecified
Left arm - Exact position unspecified
Right leg - Exact position unspecified

2. Guide from vsquared in GitHub: https://github.com/vsquared/ECG_UNO_Processing3_2_3
H/W Config:
Ref E - Closed
3V/5V - 3.3 V
AIN SEL - A5(11,12 Closed)
D4/D9 - D4

Those two guides give completely different configuration. So, my questions are:
1. What is the H/W best configuration to get EMG signal?
2. Where is the best electrode placement to get EMG signal while clenching your hand (for example)
3. What is AIN_SEL and D4/D9? Is it important to choose which one?

Thanks

[LubOlimex]

The two guides use different main boards. Our guide uses OLIMEXINO-328, the second guide uses Arduino UNO. The configuration of the jumpers depends on what main board you are using.

There is no best jumper setup. There is no best electrode placement. It all depends on the specifics of your setup and what you want to measure.

If you want to measure EKG - probably it is best to use both arms to acquire signal and place the DRL on the right leg (DRL actually comes from "right-leg driver").

>>> What is AIN_SEL and D4/D9? Is it important to choose which one?

AIN_SEL is the analog pin where the shield would send the data it acquired. If you have two or more shields stacked - each should have AIN_SEL set to different position.

D4/D9 jumper controls which digital pin the shield should use for acquisition of calibration signal from the main board. If your main board uses D4 for other purposes, then change it to D9, and vice versa.