No Serial Response From Spartan 3 Lite OEM

1

This is the output that I am sending to the Spartan (8n1, 9600B):

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Brand new LSU4.9, the sensor is pre-heating and I’ve triple checked the wiring between the Spartan and sensor. I’m not getting any response from the Spartan, just a constant 5V.

Is there anything I could be missing or that I should check?

2

I tired another Spartan and two other serial devices, but am still not getting any response. I traced the Rx Tx pull resistors to USB_VBUS on the M452LC3AE, but I haven’t been able to find to which pin the side is connected to on any of the 3 Spartans I have.

Pin 13 is grounded.

3

I determined the issue. For anyone experiencing the ‘issue’, sent commands must be followed with line feed.