Improve GATT Serial Transport message handling #15
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lib/Bean.js - Bean.prototype.send - CRC part of GST buffer (gstBuffer) - gstBuffer sliced to 19-byte chunks (->gstChunk[]) - the chunks then sent via SERIAL_UUID BLE characteristics
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BLE characteristics transport mechanism limits message length to max 20 bytes. This, in combination with GATT Serial Transport message format of BLE Bean, provides sufficient space for max. 15 characters in one single serial message (in an non-fragmented GST buffer, as implemented by the current algorithm). Attempts to transport longer messages not only fail (as expected), but such malformed messages also appear to trigger bugs in the Bean firmware (so that, ultimately, an affected Bean needs to be cold-restarted).
The modification updates algorithm to the desired state: message payload is split to 19-byte chunks, which are then sent in a sequence as defined by the Bean GST protocol specification.
lib/Bean.js - Bean.prototype.send