Hi.
Our system uses SJA1105QEL ethernet switch (Host is MPC5748G).
I want to read configuration value. so i tried to access address 0x00000000 (ETH_DYN 0x00h) but the result of read access is same as write access (SDO is mirrored as SDI).
According to the software manual, i understand that first 32 bits are access control value and next 32 bits are ignored value for reading data.
So, i tested following method in S32 project.
-test code
-result
Do you think this method is wrong or other problem exists?
please any help for me.
best regards.
thank you.
Solved! Go to Solution.
Suggest to write this register firstly then read it to verify the content.
Dear guoweisun.
i already wrote static configuration data such as below before read access.
do i need anything else?
best regards.
You can read your written content now?
where write access, the data is transmitted via SDO.
i can read buffer after write access.
buffer has mirroring data from SDO same as SDI.
Refer to this timing format!
Yes,please follow the timing !
I solved this issue.
i think it was SS signal problem.
i should have checked Continous SS option in S32DS.
thank you for your help a lot.
best regards.
you mean i need to insert delay time between first 32 bits and second 32 bits for t3?
Data (containing the number of 32-bit quadlets to be read and address to read from) is
received on the SDI input of the switch and is treated as a sequence of 32-bit quadlets.
Data corresponding to the address received is output on SDO pin of the switch.
Dear guoweisun.
thank you for your reply.
In my case, i want to read a register value at 0x00.
Where read access, i understand first 32 bits are mirrored same data via SDO.
I expect to read next not mirrored 32 bits data via SDO. but the next 32 bits are also mirrored SDI data.
i think it is something wrong.
is my test code wrong or not?
best regards.