Communications-Protocol-XMTA-JK408-4-channel-temperature-controller-YUYAO-GONGYI

• XMTA-JK408_4_channel_temperature_controller_-_YUYAO_GONGYI

XMTA-JK408 communication

1．interface The meter with 232 and 485 two types communication interface.Use 232 communication interface only contact one meter,three wires contact and the transmitting range is about 15m.If use the 485 communication interface must have one piece of 232-485 convertor,the most can contact 64pcs meter.It is two wires contact and the transmitting range is about 1000m.

2．Commucation agreement

• ⑴communcation baud rate was 1200、2400、4800、9600 four kinds can modify，the data format is one start bit、eight data bit，two stop bit，no checkout bit.

• ⑵Read order

（address code +80H）+（address code +80H）+52H（read）+（the parameter code need to read）+（00H）+（00H）+ channel NO.（1～4） + ( checkout and （first seven byte summation /80H’s remainder）

Similarities with WuxiGold: READ : Wuxi: address code + 52H (82) + code of the parameter to be read + 0 + 0 + ECC Wuxi

• a- add the address to 80, send the address twice.
• b- tell it read next with 52H / same as Wuxi
• c- parameter to read
• d- 0 0 placeholders
• e- they had to add the channel designator!
• f- modulus is different! they divide by 80H

• ⑶Write order

（address code +80H）+（address code +80H）+〔57H（write）〕+ （the parameter code need to write）+（the highest eight byte parameter）+（the lowest eight byte parameter）+ 〔channel number（1～4）〕+〔checkout and （first seven byte summation /80H’s remainder）〕

• ⑷The meter return

   （the highest eight digit of measured value）+（the lowest eight digit of measured value）+（the highest eight digit of parameter value）+（the lowest eight digit of parameter value）+（output value 0～100）+（status byte）+〔channel number（1～4）〕+〔checkout and （first seven byte summation /80H’s remainder）〕

• ⑸when the meter write,the program segment should according to the meter’s specification to add parameter amplitude limiting function so as to avoid the data exceed the range writed into the meter.the parameter refer to the meter parameter sheet series.

• ⑹The read and write order intervening time need more than 0.3s.

⑺If the meter not output the decimal point information,accord the request to set. ⑻Measurement value is（7FFFH）means HH（upper limit overflow），is 32512（7F00H）means LL（lower limit overflow） ⑼Other ① Each frame has 8 bytes,double byte all high byte in front,low byte in the rear. ② The meter alarm byte: 0 0 0 0 0 0 AL1 AL2 Position condition=1 is alarm，=0 is no alarm