Receiving strings from a smart motor

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1

I’m trying to send a cycle count from a Moog smart motor to an ADM1602U LED but only get garbage out.

How do I set up the LED to receive ASCII strings? What I send is visible in the motor’s software, but gets garbled up in the display.

Any help is greatly appreciated.

Thanks

2

Have you matched the Baud rate and other parameters with the Moog smart motor?

Default for the LED is 9600 N-8-1

3

Yes, they match. I currently have output from the motor at pin 10, which is the RS-232 transmit channel. The motor is an SM23375DM. +5 on pin 12, ground on 13.

4

I’m unsure what you’re saying:

output from the motor at pin 10, which is the RS-232 transmit channel

I guess that's the motor's pin 10?

And it may well be the motor’s transmit channel - is it connected to Rx on the LED?

Maybe the motor is not working with 5 VDC?

the datasheet clearly states:

Note that the RX input should be a 5V TTL-level signal directly from a 5V microcontroller or other 5V system. You should NOT connect the board to RS232-level voltages, which are +/-10V and will damage the board (see our explanation here). If you do wish to connect this display to RS232 signals, you can use a level-shifting board such as our PRT-00449 to translate the RS232 signals to TTL-level signals.

that could be affecting things.
5

Yes, I have 5 V at the motor, between pins 12 and 13. I see in your response that I need a “shifter” to translate the signal. I’ve purchased one(1568-1283-ND), but am unsure how to wire it.

Please correct if I’m wrong: from the motor to shifter - 5V out (pin 12) soldered to Vcc @ the back of the shifter

  • Gnd to gnd

  • pin 10 (transmit) to Rx-1

then, from LED into matching female shifter ports?

Again, thanks for the assist!

6

Aside from making certain that you also have GND connected to the LED, I would try connecting the motor to a serial port on a PC and using HyperTerminal to verify the communications work with what settings you believe the motor is configured with.

I’m not sure you need the level shifter for motor to LED connection since you motor is using 5VDC.

You may need the level shifter for connection to the PC since the PC likely uses somewhat standard +/- 13VDC or so.

RS232 levels can vary from +/- 3VDC to +/-25VDC.

I have not used a level shifter but your description of the connections seems correct.

7

There are a bunch of notes about this and that in the tutorial for the LCD display.

It seems there can be a number of reasons why it may show garbage.

https://www.sparkfun.com/tutorials/246

8

Great !!

I have it working, but it’s filling up the display. I need to figure out what command clears the previous entry.

It’s probably code hiding in the manual somewhere for me to pass by it again and again!

Thanks for all the help !!

I’m checking the FAQ for how to give “kudos.”