topic Re: U0_RTS - driving RS485 in LPC Microcontrollers

U0_RTS - driving RS485

lpcware — Wed, 15 Jun 2016 20:09:20 GMT

Content originally posted in LPCWare by Wojtkingson on Tue Feb 10 11:16:50 MST 2015
Hi,

I want to drive my RS485 transceiver by U0_RTS, I´ve managed it by software, but I would like to do it by hardware.

Some of my steps:

Chip_SWM_MovablePinAssign(SWM_U0_RTS_O, 1);

Chip_UART_ConfigData(LPC_USART0, UART_CFG_DATALEN_8 | UART_CFG_PARITY_NONE | UART_CFG_STOPLEN_1 | UART_CFG_LOOP);

This code works fine but I cant receive anything from UART. Whenever I remove UART_CFG_LOOP, U0_RTS on PIO_01 doesn´t work anymore. I´ve tried lot of variations, but still without succes. Signal si controlled by oscilloscope, so there is problem only with pin with U0_RTS signal (I think).

Re: U0_RTS - driving RS485

lpcware — Wed, 15 Jun 2016 20:09:20 GMT

Content originally posted in LPCWare by ramniraj10 on Sun Mar 15 22:14:31 MST 2015
Dear Wojtkingson ,

Have you checked the DIR pin of RS485 trans-reciever ic.

You an check the conenctions of RS485 in internet as how it works.
This DIR pin is ued to set up the trans receiver in Tx or Tx mode.

Thanks,
Niraj Ram

Re: U0_RTS - driving RS485

lpcware — Wed, 15 Jun 2016 20:09:21 GMT

Content originally posted in LPCWare by Wojtkingson on Mon Mar 16 02:31:10 MST 2015
Hi,

thanks for reply. I´ve checked state of DIR/RTS pin (pin which should control TX/RX) with oscilloscope and it didn´t work. I guess, that problem is somewhere in my setting.