Bangle.js 2 Cutting Edge - new heart rate algorithm

That's great, thanks!

Actually it seems I couldn't email you the zip so I'll attach it here. It's mostly in Chinese so it can be a bit tricky to dig through, but:

• The binaries and header are in VC31B/algos/SPO2 so you need to add those to https://github.com/espruino/Espruino/tree/master/libs/misc/vc31_binary
  
• Then you need to link them in by copying the form of the existing HRM algo: https://github.com/espruino/Espruino/blob/master/boards/BANGLEJS2.py#L77
  
• In VC31B/VCHR02Driver_HrSpo2_Gsensor_V1.9.5/module_heart_vc_int.c the algorithm is called, but you need to look into the other files in that dir for how to configure the sensor.
  
  

One of the important bits is probably:

		case VCWORK_MODE_SPO2WORK:
			regConfig[0] = 0x47;
			regConfig[1] = 0x2F;
			regConfig[6] = 0;
			regConfig[7] = 0x80;
			regConfig[13] = 0x96;
			regConfig[16] = 0x04; // OverSample
			break;

Which you need to get put in https://github.com/espruino/Espruino/blob/master/libs/misc/hrm_vc31.c#L767-L776 when SPO2 mode is to be enabled.

Right now we don't auto-calibrate the HRM speed which their code does - I'm not sure if that's going to end up causing problems or not.

1 Attachment

• VC31 & VC31B drivers.zip