CP2112 occasional send two STARTs on Write Request.
I am using CP2112 for I2C communication with a slave device.
The slave device sometimes did not accept communication correctly about once every 10 times.
At that time, only the same Write Request is sent periodically.
When checking the communication waveform with an oscilloscope, CP2112 occasional send two STARTs on Write Request.
The behavior is the same as the thread below.
I also read the errata, but I can't find out issues with the Write Request.
I have three questions.
1.Is the first 3 letters of the 3rd line printed on the chip a revision?
2.Does CP2112 of revision F03 have the problem that occasional send two STARTs on Write Request?
3.Is there a way around this problem?
Thank you for contacting to Silicon Labs technical support regarding to CP2112 product.
My answer as below:
Anyway, to understand more about this problem, could you please provide us some information as below:
Thank you for your reply.
1.I'm using MM-CP2112A.
2.I'm using an Excel macro.
I Attach the Excel file.
Also I recorded the communication waveform when NG occurs in the Excel file.
3.My environment : Windows 10 Pro 1909
I have a question.
1.Is there a way to check the revision?
I found out a Version in HidSmbusExample.exe. Is this a revision?
Sorry, I'm not found this board schematic on this pages. Could you please attach this schematic into this thread?
Anyway, I've tried to reproduce this on our environment, but we can not do this, there is no issue appeared. Could you please share to me some information about your SLABHIDtoSMBus.dll file? Where do you get this file? Is this from Silicon Labs website? Could you please try to test with the SLABHIDtoSMBus.dll file in the following package (below)?
About the Hardware Revision, according to Figure 1.1. CP2112 Part Numbering, you can get this Firmware/Hardware Revision through this information. And, there is three ways to get this part numbering:
Thank you for your reply.
Due to rights issues I can't upload the schematic.
You can download the schematic by registering as a member.
There is the schematic in "取扱説明書".
I downloaded the SLABHIDtoSMBus.dll file that is included in excel_macro.zip from Silicon Labs website.
(But I downloaded the file about a years ago. So I don't remember much about that time.)
I tested with the new SLABHIDtoSMBus.dll file from USBXpressHostSDK-Win.zip.
But there is a same issue appeared.
According to HidSmbusExample.exe, The Firmware Revision of my CP2112 is 02.
So I buy a CP2112-F03-GMR from Digi-Key.
I'll exchange CP2112 on my board to CP2112-F03-GMR and try it again.
Thank you for your information.
Please try to test this on CP2113-F03-GMR firmware version, then provide us this result. Hope it works.
Today, I got CP2113-F03-GMR from Digi-Key.
I exchanged CP2112 on my board to CP2112-F03-GMR and try it.
CP2112 have not sent two STARTs on Write Request.
I was able to solve the problem.
Thank you for your advice so far.