Multiplexing encoders over to JP4 and JP6 provide single ended

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mnova_user
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Joined: Sun Mar 30, 2025 12:41 pm

Multiplexing encoders over to JP4 and JP6 provide single ended

Post by mnova_user » Fri May 02, 2025 4:11 pm

After the command for multiplexing was executed, the JP4 and JP6 will admit 5V single ended on the inputs.

// Mux encoder inputs from KFLOP JP7 & JP5 to JP4 aand JP6
FPGAW(ENC_NOISE_FILTER_ADD) = ENC_0_3_JP4 + ENC_4_7_JP6 + ENC_NOISE_FILTER_DEFAULT_VAL;


After rebooting the controller config of JP4/JP6 is still the same and still accepting 5V right?

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TomKerekes
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Re: Multiplexing encoders over to JP4 and JP6 provide single ended

Post by TomKerekes » Fri May 02, 2025 4:31 pm

Yes either by rebooting or writing to the FPGA Resister without the multiplexing bits and just the Noise Filter Value will disable the multiplexing.

Actually the inputs can be used as General Purpose inputs whether or not the encoder counters are connected to the inputs.

Note JP4 and JP6 are 3.3V LVTTL signals and should never be driven over 3.8V. Most 5V driver devices do not do this as the requirement for a 5V TTL high level is only 2.4V.
Regards,

Tom Kerekes
Dynomotion, Inc.

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