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Can you please let me know if there is a point where you make transfers larger than 4MB in one transfer? What is the Windows build number in which you are testing?
first, thanks for the quick respone!
We ran the tests on two different PC's with getting the same result (sporadic data lost).
Build No. of PC#1 is: 17763.379 / PC#2 is 17763.253.
Our transfer size is normally around 5MByte (but I did also up to 10MByte in the past with cyUSB3.sys-version 22.214.171.124 without any problems)...
But here seems to be a possible reason for the issue...I am just running a test with 4MByte transfer size and a heavy loaded CPU...no data lost (actually..) appears!!...
So my question is: what is the reason for the 4MByte limit?..because there is no information at all in the Cypress driver documentation about this limitation.
And where is the difference regarding transfer size limitation between the two CyUSB.sys versions (126.96.36.199 vs. 188.8.131.52)?
Thanks a lot in advance for your effort!
Can you please try the driver posted in the last response of the below thread:
As mentioned in the above thread, this driver is not yet Microsoft certified and is only for Windows 10 x64 machine.
It only has Cypress digital signature.
Kindly test with this driver and let me know the result.
with the driver you've sent to me (184.108.40.206) , I have the following results:
- when using transfer size 4MByte, the behaviour is normal (like 220.127.116.11/18.104.22.168)
- when using larger sizes (5MB), there will be no data transferred at all and the function returns immediately without any errors.
We also discoverd that our second testbench (with the windows-build 17763.253) still has the issue on CyUsb3.sys-V22.214.171.124 even when using maximum transfer size of 4MByte...this is strange..
For USB2 device, the maximum transfer size over Bulk Endpoint would be 4MB even with this new driver.