RANDY KELSO

RS485 using UART module on MCF52259 family

Discussion created by RANDY KELSO on Aug 27, 2009
Latest reply on Aug 27, 2009 by Mark Butcher

Hello, I am trying to implement an RS485 interface between several 9S08s and an MCF52258 as bus master. The Processor Expert Asynchro Serial bean worked great on the 9S08s. But I am running into trouble on the coldfire part because I don't see anyway to trigger an interrupt when the transmission is complete, at whichpoint I need to switch the RS485 transceiver back to Rx mode as quickly as possible. Maybe the chip designer's intention was for us to use the RTS signal, however this would require me modifying my PCB and adding an inverter.

 

Has anyone really liked their implementation of the TX/\RX\ RS485 transceiver signal using the Coldfire UART module?

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