EEVblog Electronics Community Forum
Products => Test Equipment => Topic started by: kenkit on December 05, 2024, 08:05:37 pm
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The SDS1202X-E has 2 channels and supports upto 200mhz with 100,000 wfm/s (normal mode), and 400,000 wfm/s (sequence mode)
vs the DHO812 with 2 channels with 100MHz and 1000,000 wfms/s.
I intend to use it in electronic projects e.g find clock lines on phone repair emmcs and also debugging spi/i2c signals mostly in phone/laptops etc.
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The Rigol has better specs than the Siglent, but don't buy the DHO812, for the same price you can get the DHO804 with 4 channels and then upgrade its bandwidth. An upgraded Siglent SDS802X-HD may also be a good choice in this price range.
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... also debugging spi/i2c signals mostly in phone/laptops etc.
You probably need 4 channels for SPI.
But either way: Don't buy the expensive model, buy the base model and change it to the expensive one. The hardware is the same, it's just a configuration file on the internal disk.
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... also debugging spi/i2c signals mostly in phone/laptops etc.
You probably need 4 channels for SPI.
Not technically correct when a DSO provides a Clock Timeout setting for protocol decoding which SDS1202X-E does.
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Not technically correct when a DSO provides a Clock Timeout setting for protocol decoding which SDS1202X-E does.
SPI is usually "more than two" wires.
(and even Siglent doesn't make a 3-channel model, so four channels it is)
PS: Rigol has triggers, too, believe it or not.
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Not technically correct when a DSO provides a Clock Timeout setting for protocol decoding which SDS1202X-E does.
SPI is usually "more than two" wires.
Sure but you only need 2 to decode it ! :P
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Sure, so long as you don't mind constantly switching probes between MISO and MOSI while mentally reassembling packet sequences in your head.
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SDS1202X-E
SDS1104X-E and you hack/upgrade it to 200 MHz plus 4 channels, the price I believe the same more or less, 100 bucks difference. But do look at newer models from Rigol and Siglent, like said above. You want 4 channels, and ability to hack/upgrade.
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Any scope will do the job if you only need to check the presence of clocks and the communication between chips. Also 8 bit vs 12 bit doesn't matter.
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Any scope will do the job if you only need to check the presence of clocks and the communication between chips. Also 8 bit vs 12 bit doesn't matter.
Yes, if you don't need to decode the data then either will do.
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Thank you for your advice, I will go for the DH0804 For the four channels then maybe hack it to 100mhz.
The Siglents are also heavier in terms of volumetric weight shipping so they would cost me more to get them here.
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Not technically correct when a DSO provides a Clock Timeout setting for protocol decoding which SDS1202X-E does.
SPI is usually "more than two" wires.
(and even Siglent doesn't make a 3-channel model, so four channels it is)
PS: Rigol has triggers, too, believe it or not.
I think Rob is telling you that you don't need to probe CLK, the DSO can be told the timeout in order to decode using just the data channel. If that's the case, you only need 2 channels, one for MISO and one for MOSI, and set an appropriate clock timeout.
I might be wrong.
Regards,
Josh
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Here is a demonstration of decoding SPI with two probes using the clock timeout trigger. Only one of the I/O channels (MISO or MOSI) can be probed as the clock is needed for the trigger and decode.
- https://www.youtube.com/watch?v=izu33UtIyyY (https://www.youtube.com/watch?v=izu33UtIyyY)
As Fungus said, this isn't ideal if you need to decode I/O in both directions, but often you only care about one direction. For example, an LCD controller (https://www.nxp.com/docs/en/data-sheet/PCA8546.pdf) might only have commands and data sent to it for initialization and display. A sensor (https://prod-edam.honeywell.com/content/dam/honeywell-edam/sps/siot/en-us/products/sensors/pressure-sensors/common/documents/sps-siot-spi-comms-digital-ouptu-pressure-sensors-tn-008202-3-en-ciid-45843.pdf?download=false) might only send data for whatever is being sensed and accepts no commands.
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I think Rob is telling you that you don't need to probe CLK, the DSO can be told the timeout in order to decode using just the data channel. If that's the case, you only need 2 channels, one for MISO and one for MOSI, and set an appropriate clock timeout.
How can you decode the data if you don't know where the bits are?
eg. I could send 0xff 0xff 0xff 0xff, how would you decode that without a clock signal?