problem: the project needs to develop 485 serial communication on the android panel. The serial port needs to be monitored after the read command is sent, and the communication is not considered to have failed after N time. Use java s FutureTask with F...
recently, after writing a PLC communication protocol, I sent it a command to read 1 byte after the address 0x0000 (the address 0x0000 exists in PLC, and sent successfully, and the data sent is correct), it should send me 12 bytes (including ACK, site nu...
problem description Open two serial ports at the same time in Android environment, one of them receives the instruction and sends the instruction to the other, but the command of the second serial port will block and often return garbled or the two in...
is using RXTX to write its own communication protocol. At present, one of the problems encountered is: a sends data to B, assuming that the header data of frame I received by B fails to pass, and B requires A to resend, so how can I correctly deal with ...
reason R2D bought one with a capacity of 1T when it first came out. description except for being a router, everything else is chicken ribs, which feels useless, and the offline download function is not easy to use expectation is there a raspbe...
how does js add one function to another ...
assume the data table relationship: order order data sheet: order_id public_order_id 1 AAA 2 BBB 3 CCC prod goods data sheet: order_id prod_id 1 100 1 101 1 102 2 101 2 103 3 102 3 104 Front end display AAA BBB CCC when...
has made a login page. At present, only the user name and password are encrypted and the key is agreed with the background to be passed to the background, but the user name and password of the input box can still be seen in the element. I saw that the u...
start the bitcoin Synchronize command RPConerpc, 123 bitcoin -server -printtoconsole here are some logs 2018-04-16 01:49:10 addcon thread start 2018-04-16 01:49:10 init message: Done loading 2018-04-16 01:49:10 opencon thread start 2018-04-16 01:49:...