[issue #914] _P053_PMSx003 Dust Sensor looses sync #976
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TD-er
commented
Feb 28, 2018
TD-er
commented
- Use peek instead of read, to make sure a complete packet is in the buffer.
- Flush buffer after processing a packet.
- Increased software serial buffer to the size of 3 packets.
- Peek (+ read garbage) 10 times per second to get the buffer in sync to start with start byte of packet.
- Decent delete + clean up of software serial allocation when changing settings (prevent memory leak)
- Move log String allocation to inside scope of function, not permanent allocated.
- Split into separate functions to make it better readable.
- Use peek instead of read, to make sure a complete packet is in the buffer. - Flush buffer after processing a packet. - Increased software serial buffer to the size of 3 packets. - Peek (+ read garbage) 10 times per second to get the buffer in sync to start with start byte of packet. - Decent delete + clean up of software serial allocation when changing settings (prevent memory leak) - Move log String allocation to inside scope of function, not permanent allocated. - Split into separate functions to make it better readable.
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It is better to check also if dummy (marker) is exactly 0x424D, if not we don't need to try calculate checksum. Looks like problem was because always take 2 bytes from buffer and datagram has even bytes so it is impossible to find sync if miss one byte. |
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That's a good suggestion. (it was past 2am) |
Quickly commit + merge is never a good idea when some visitors arrive... Fixed now.
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OK, test begins. |
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@micropet OK to merge it? |
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Unfortunately, no. There were about 60 minutes of data delivered. |
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But it is not worse than before? |
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Yes you are right. This version also runs longer than the old version. |
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I've been running this version on an ESP32 and STMF4 board for many months now. She has never failed. Maybe it gives you an idea. #include "serialReadPMValue.h" int length = serialRead(Serial1,receiveDat,receiveDatIndex,5); //change the serial port:Serial1,Serial2.. if(length&&checkSum) |
