Data sniffer with Bluetooth module

This is a follow up from this discussion here (https://github.com/daturach/Documentation/wiki/Data-sniffer-box)

If you don't have enough PC COM ports, you can replace one with a bluetooth module. I am using an HC-05 you can find easily and they are cheap enough.

They need 5 VDC supply but their logical levels are from 0-3.3 VDC. It's important to know that because their inputs are not 5 volts tolerant, at least I did not find any info about this topic. So we assume they are not tolerant to 5 VDC !

We need as well a couple of RS232 to TTL level converters (available in quantity and cheap). These 2 modules are powered at 3.3 VDC. It's again important so that their data (RXD/TXD) voltages match with the HC-05 module input/output levels.

The DUT device you are going to connect to should have 0-3.3 VDC levels.

Note 1: Don't forget to wire the ground between your DUT and your power supply :-)

Note 2: I powered the HC-05 with 3.3 VDC and it worked. This was to program it with a Teensy board. For this current project, better stick to 5 VDC.

Note 3: DC/DC converters: they are everywhere, just google it!

Schematics: (with the sniffer box schema)

Everything in a box with the converter

Together with the data sniffer box: It matches perfectly :-)