EEVblog Electronics Community Forum
Products => Test Equipment => Topic started by: eti on October 20, 2020, 03:13:10 am
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Forgive my ignorance, I am probing the output of the COB IC of my "Kaiweets" HT118A DMM, hoping to find RS232 being pumped out, and I came across this waveform (pin # impossible to know, since it's COB)... does anyone recognise this?
{Update}: I've attached a zipped pulseview session too.
Thanks!
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Gosh, no one? ;)
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Gosh, no one? ;)
Looked yesterday and all I could see was several clock bursts. :-//
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Gosh, no one? ;)
Looked yesterday and all I could see was several clock bursts. :-//
Thanks for looking :) - I have captured more in "PulseView" and applied the "UART" filter - how does one know how accurate said filter is, though? Is there some form of file format I could share here, to make the full capture more accessible to people who could ID the pulses?
Cheers!
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Is this any more meaningful?:
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This doesn't look like UART at all. Should be a clock line of some synchronous bus transferring 8-bit values (8 shorter pulses separated by a longer one). Are there any other signals belonging to the same bus? (i.e. other pins of the same connectors or PCB pads grouped together with this one). Look for a data signal clocked by this line (some less regular signal with a frequency <=1/2 of this clock, with all transitions during the same clock levels).
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This doesn't look like UART at all. Should be a clock line of some synchronous bus transferring 8-bit values (8 shorter pulses separated by a longer one). Are there any other signals belonging to the same bus? (i.e. other pins of the same connectors or PCB pads grouped together with this one). Look for a data signal clocked by this line (some less regular signal with a frequency <=1/2 of this clock, with all transitions during the same clock levels).
I'll look, thanks. But if it's not UART, why does the UART filter seem to (sort of) decode it?
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This doesn't look like UART at all. Should be a clock line of some synchronous bus transferring 8-bit values (8 shorter pulses separated by a longer one). Are there any other signals belonging to the same bus? (i.e. other pins of the same connectors or PCB pads grouped together with this one). Look for a data signal clocked by this line (some less regular signal with a frequency <=1/2 of this clock, with all transitions during the same clock levels).
It might be just be the clock line of an SPI bus whilst transmitting a multi-byte message.