Fleker
commented
6 years ago This might be a bug in the UsbSerial library.
But in general, you should expect UART data to come in intermittently. Although it may stream continually, the interrupts may be fired at any point. You should buffer the data and determine the stop point on your own, then process it.
Generally, embedded engineers will do several different steps to properly segment the data:
- Use a fixed size, ie. assume every packet is 3 bytes
- Send a fixed-size header which contains information about the data such as the total length and perhaps error correction information
- Send the length of the packet as the first byte, allowing the receiver to count that many bytes (with a max of 255 characters)
- Send a stop character at the end of your data transmission, ie.
0x00. This is more useful if you're sending strings. Many systems append a null character at the end of strings internally to denote that you have reached the end.
mahermeg17
Hi, I'm using this sample code with a PICO PI IMX6UL. The problem is when I send a String like "abcdefghijklmno". I receive it on the other side divided, it means not as a single string, like "abc" then "de" then "fghijk" then "lmno". And messages are received into random way, not the same number of parts, and not the same length of each part. My UART config is as following: BAUD_RATE = 115200; DATA_BITS = 8; STOP_BITS = 1; CHUNK_SIZE = 256; and PARITY_NONE
On the other side, I use UsbSerial library on an android phone (https://github.com/felHR85/UsbSerial)
No problem when reading data. I need to read data in one piece. Any help please! Thanks.