S120 scanning can not be sustained

RE: S120 scanning can not be sustained

YeLun — Mon, 01 Dec 2014 01:07:08 GMT

Thanks a lot for you help.

RE: S120 scanning can not be sustained

YeLun — Fri, 28 Nov 2014 01:24:46 GMT

Ah! Before your answer, I have already suspect the scan_window and tried "m_scan_param.window = 0x009F; ", it was not work correctly. Ok, let me try "0x009E".

If there always need to minus 2 from scan_interval? And minus 2 mean 1.25mS, may be miss one pack. Could you tell me why minus 2?

if I need scan_interval be 0X3E8(1000mS), scan_window will be 0X3E6(998.75mS), Is that right ?

RE: S120 scanning can not be sustained

Petter Myhre — Thu, 27 Nov 2014 12:31:03 GMT

It is a bug with the S120, you can't have the scanning window equal to the scanning interval.

A workaround should be to decrease the scanning window slightly, please try 0x009E instead of 0x00A0.

m_scan_param.interval     = 0x00A0;  // Scan interval.
m_scan_param.window       = 0x009E;  // Scan window.

@boyu: I don't know the details behind why it is 1.25ms, but somehow the scanner doesn't have time to restart.

I have done some testing, and it seems that 1.25ms is enough, or minus 2 as you say. But 0x3E8 is not 1000ms, because it is 0x3E80.625ms = 10000.625ms = 625ms.

You should use:

m_scan_param.interval     = 0x0640;  // Scan interval.
m_scan_param.window       = 0x063E;  // Scan window.