I’m kinda new to this stuff so please bear with me. I’m trying to create a game that uses Heart Rate data as an input using Hackvision in conjunction with the Polar Heart Rate Monitor Interface. Ideally, I’d like to plug the heart rate monitor interface into some of the analog inputs of the hackvision.
Unfortunately, the best instructions I’ve found in hooking up the heart rate monitor interface with an arduino mention using I2C mode, using pins A4 and A5 which are the designated SDA and SCL lines, respectively.
Does the hackvision have designated SDA and SCL inputs? Any help would be greatly appreciated. Thank you!
Yes, pins A4 and A5 are broken out as part of the nunchuk connector. See the circuit board images.
A Wii nunchuk also uses I2C communication. It was really tricky to get the nunchuk to work with Hackvision because the constant interrupt generation to make the video signal interferes with I2C. I trimmed down the size of the I2C library and it is now part of the Hackvision controllers library. See the nunchuk controller code for some ideas on how to use it. Basically, the code waits for the vertical blanking interval at the end of a frame to perform the I2C communication.
Timing issues make it tricky…if your heart rate monitor responds quickly, then it will be easier to do. Sounds cool!