I am looking into getting a Saleae logic analyser for a project to reverse engineer an electronic display and buttons for use with a RaspberryPi.

I think it should be OK as I would doubt, by my own assumption, that the voltages involved come anywhere close to the max +/-25V allowed for the Saleae.

I'd like to be 100% sure though, so you you think it would be standard practice to get a multimeter as well? I have been researching the specs as I'd need something that can show me the peak value of the voltage as the voltage outputs I am analysing will vary because they will have a voltage for 0 and 1 and there will be analogue outputs for audio too.

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    \$\begingroup\$ really, a multimeter is handy in soooo many situations. Imagine something does not work. You can use it to check the supply voltage, for example. However, for the serial communication, multimeters will be next to useless. They're not designed to measure max values of digital buses. \$\endgroup\$ – Marcus Müller Jan 27 '17 at 14:49
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    \$\begingroup\$ Agreed with @MarcusMüller, and to add to his point there are very cheap ones on eBay (< $10) that you can get for some rough measurements. \$\endgroup\$ – Jim Jan 27 '17 at 14:49
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    \$\begingroup\$ You cannot be 100% sure even when using a multimeter because short pulses of 50 V will not read as 50 V on the multimeter but could damage your logic analyser. In this case you would need an oscilloscope to be sure. But in practice I would just look at the design of the (display) device and can then judge on what voltage it will be running. For example by looking at the voltage rating of the supply decoupling caps. I could then confirm the voltage with a multimeter. There a multimeter is OK as a supply voltage is DC (not pulses). I agree with the others, buy a multimeter anyway. \$\endgroup\$ – Bimpelrekkie Jan 27 '17 at 14:51
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    \$\begingroup\$ Also, ground fault currents can certainly damage the LA and the PC it plugs into so a multimeter can check 0 volt differentials before you connect the input harness. \$\endgroup\$ – Andy aka Jan 27 '17 at 15:01

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