GETH SWR bit not switching back to 0

Tip / Sign in to post questions, reply, level up, and achieve exciting badges. Know more

cross mob
User19909
Level 3
Level 3
First like received
Hi guys,
I am using TC397 step B ,while initializing the Eth driver, the bit SWR of DMA_MODE is set to 1 and never returns to 0,this bit is normally set by software during init but it should've flipped to 0 after reset is complete but it isnt, I checked the MCU ref eth clock and its configured,P11.5 and P11.2 seems to be configured and working fine, what else should I check or could be causing this synchronization issue?.
Thank you.
0 Likes
4 Replies
MoD
Employee
Employee
50 likes received 500 replies posted 100 solutions authored
Make sure that the reference clock from external is available. You must measure this clock. If the clock is not available then the SWR bit will never changed to 0 after setting, reset will not completed.
0 Likes
User19909
Level 3
Level 3
First like received
MoD wrote:
Make sure that the reference clock from external is available. .


what do you mean to make sure that the reference clock is "available"? I checked that MCU GETH clock is configured and CCUCON5 i can see the configuration for the clock and I can see P11.5 the clock pin blinking,is there something else I should check?
0 Likes
MoD
Employee
Employee
50 likes received 500 replies posted 100 solutions authored
You need a 125MHz clock from external on P11.5. I don't know what you mean with pin blinking. Which board you use?
0 Likes
User19909
Level 3
Level 3
First like received
Iam using a lauterbach debugger, the 125 MHz is connected to P11.5, what i meant by blinking is in the debugger i can see the pin switching between high/low, but still it seems there is a synchronization issue, is there something missing other than initializing P11.5 as input and connecting the 125MHz to it?
0 Likes