Guide me please how to add such device support - Tasi TA612C (4 channels K/J Thermometer)
http://www.china-tasi.com/m/view.php?aid=97What I've already figured out as for its protocol. The devise uses CH340 USB-to-serial interface so we basically have a /dev/ttyUSB0 when connected to my Linux box. It operated on a speed 9600.
We should send a fixed 5 bytes request:
aa 55 01 03 03
and the device responds with 13 bytes (fixed length) response:
55 aa 01 0b f4 00 16 01 16 01 de 00 0b
Where first 4 bytes are always identical and probably can be discarded.
Next 8 bytes are 4 temperature readings:
f4 00 16 01 16 01 de 00
which stand for each channels temperature in Celsius:
24.4 27.8 27.8 22.2
Each 2 bytes pairs have Little-endian order, so first pair "f4 00" stands for 244 and at the end (244/10) to decimal 24.4 Celsius.
Last single byte - probably some checksum, but I'm not able to figure out what method is used, so we could ignore it.
Let me add a few examples of response for different readings, including when some or all probes are disconnected, which are read as NULL on original crappy software:
55 aa 01 0b f7 00 4c 01 11 01 ec 00 4d
24.7 33.2 27.3 23.6
55 aa 01 0b ef 00 e0 00 02 01 eb 00 c8
23.9 22.4 25.8 23.5
55 aa 01 0b 60 6d dd 00 ff 00 ee 00 a2
null 22.1 25.5 23.8
55 aa 01 0b 62 03 60 6d 60 6d 60 6d d7
86.6 null null null
55 aa 01 0b 2d 06 60 6d 60 6d 60 6d a5
158.1 null null null
p.s. so, "60 6d" -> 28000 -> 2800.0 C. Kind of max/impossible temperature and should be classified as NULL.
If you could suggest me an example of an existing supported similar device for Test Controller, it would help me to develop/replicate support for my Tasi device.