The SparkFun Transceiver Breakout - RS-485 does not provide output unless I leave RX open on a open trace or with an open wire and then after a few seconds there is no output. I do not understand why this pin needs to be left open. I can not just leave the pin unconnected on the board itself. I must connect to a breadboard to an open trace or attach a jumper wire left open for it to provide the differential output. If I ground the pin no output is seen on my oscilloscope.
The SparkFun Transceiver Breakout - RS-485 ships configured so that are in receive only mode until you pull the RTS pin high. When RTS is high, they go into transmit mode and will return to receive mode once RTS is low again. While in transmit mode, the board will not be able to receive any data from the RS-485 bus.
TS-Chris:
The SparkFun Transceiver Breakout - RS-485 ships configured so that are in receive only mode until you pull the RTS pin high. When RTS is high, they go into transmit mode and will return to receive mode once RTS is low again. While in transmit mode, the board will not be able to receive any data from the RS-485 bus.
I have RTS held high at 5 volts
I still have the same issues I have described
Not sure what’s causing that.
It’s the RX pin you’re having trouble with, correct? Are you able to transmit with the board>
Would you mind posting a photo of the top and bottom of your board and a diagram showing how you have the board connected to your system? I’ll need those to dig into this.
TS-Chris:
Not sure what’s causing that.It’s the RX pin you’re having trouble with, correct? Are you able to transmit with the board>
Would you mind posting a photo of the top and bottom of your board and a diagram showing how you have the board connected to your system? I’ll need those to dig into this.
I am not able to transmit data from the RS-485 output…
I want to Transmit TTL serial data to the RS-485 board from the Teensy 3.6 and get a differentiated signal at the output of the RS-485 board.
I have the two black wire connected to ground with the Teensy 3.6 and RS-485
The red wire is connected to power in the Rs-485 and 3.3 volt supply on the Teensy 3.6.
RTS is the blue wire connected to the Teensy 3.6 3.3 volt supply .
TX pin on the RS-485 is connected to the Teensy 3.6 TX pin with the brown wire.
The output A and B are sent to my oscilloscope
I get no output from the RS-485 board
I can get a briefly output when the RX pin on the 485 is attached to an open trace or open jumper wire.
TTL is the 1st picture for the oscilloscope
2nd is the output from the RS-485 board no signal is being processed
top of RS-485
Looking at the schematic, TX on the RS485 breakout is the output of the breakout. Try connecting TX from the Teensy to RX-I on the breakout, with RTS tied high as you have it.
In general, SparkFun tends to label their serial pins with a -I or -O; these indicate whether the pin is an input (-I) or output (-O) from the board in question.
/mike
n1ist:
Looking at the schematic, TX on the RS485 breakout is the output of the breakout. Try connecting TX from the Teensy to RX-I on the breakout, with RTS tied high as you have it.In general, SparkFun tends to label their serial pins with a -I or -O; these indicate whether the pin is an input (-I) or output (-O) from the board in question.
/mike
Thank you that fixed my problem!
Thanks for helping Mike, and glad you got it working Peavey!
TS-Chris:
Thanks for helping Mike, and glad you got it working Peavey!
Thanks for your help Chris