PLS62-W RS485 | Thales IoT Developer Community
July 22, 2020 - 5:42am, 3967 views
Hello
I could not find the information in the Java API nor in the Hardware manual, which one the RS485 interface is on th EHS5T RS485? (COM0, COM1, USB0, ...)
A small Java example would be helpful, I'm guessing how the write enable is handled on the RS485 chip, probably it's solved with DSR line, but I ****** find some information for that neither.
Regards,
Ítalo
Hello,
RS-485 is accessible from the module as ASC0 - RS-485 controller is connected over ASC0 inside the terminal. The lines (A+, B-) are available on the GPIO connection on the terminal as shown in the hardware description document for the terminal.
Regards,
Bartłomiej
Hello,
Thanks for you answer !!
you would have an schematic example?
My cicuirt RS 485:
Regards,
Ítalo
Hello,
I don't have any example schematic probably. In the terminal there is ***13488 as RS485 chip.
Regards,
Bartłomiej
Hello,
I can confirm that we are using ***13488 chip that supports "AutoDirection" function which really simplifies the connection to the application (only RX and TX). We can share sample schematics for this solution if you want.
With IC like ISL83483, your application need also to control manually direction/enable functionalities (so 4 lines must be controlled). In this case, you can follow schematics from the ISL83483 datasheet: right half of the circuit from FIGURE 1. But here you will also need to implement the RS485 direction control on your application side.
Please share some more details about your application, It is the PC ? or some custom Hardware? So we can help you more precisely.
Best Regards
Wojciech
Hello,
Thanks for reply, at would like some example schematics please.
My application is a custom Hardware consists of receiving what comes from ASC0, which can be RS232 or RS485 depending on the need and send from TCP and TCP from ASC0. As listed below, implement the circuit for RS485, in which GPIO 08 selects the operation **** of IC ISL834883IBZ.
As shown in the java example below, when the device is going to send something via the RS485 serial I set GPIO 08 to high, and I send the data through the Dataoutputstream, I add a stop with the size of the byte array, this method works with a response time of external application up to 100ms, below that I can't get a good performance
Best Regards,
italo
Hello Italo,
with your current solution you will have poor performance (limited by GPIO control speed).
Attached below recommended solution for RS485
Hello Tymoteusz,
I have the same problem of Italo and I have seen your advise. I have not understood wich are the components at the extreme left (100Mhz 600 0,2) if they are for the line protection it is not better to add 2 TVS? Thanks
Hello,
those components are ferrite beads, their purpose is for noise protection.
ESD/transient suppression is optional.
BR
Tymek
Hello Italo,
i have the same problem of implementing a RS485 connection using PLS62 w.
Have you done the solution that Tymoteuz (Timoteo I guess) has given.
Did you have any problem?
Thanks.
Marco
Hello m.liguori@sira.net
Sorry for the delay, because my application was finished with the PLS62-W module, but the solution passed above worked perfectly
Thanks
Italo