Time for resetting W7100A, how long?

Question

Dear Wiznet, We have developed a product Serial to Ethernet based on Wiznet W7100A. We use Pic64FJGA004 to process data, to send and receive data through uart of W7100A. We reset W7100A by belowing for loop: for(ii=0;ii<1000;ii++) for(ji=0;ji<2000;ji++); PIC24 have characteristic: 16 Millions instructions per seconds. So we think that the time to reset is about 0.125 seconds. For most of our products (70 modules Serial to Ethernet) it works well. But for some cases, it seems that 0.125 seconds is too fast. In one case, we cannot ping the module with IP 192.168.0.36. after reseting manually we can ping. After that we think that probably it would be better to lenghthen time of reseting. for(ii=0;ii<2000;ii++) for(ji=0;ji<8000;ji++); Now we use the above loop for resetting W7100A. (we think it takes about 1 second) But we are wondering: Is this way good for w7100A? Does the time of resetting affect aging of w7100A? We have read the datasheet again and again, but found no answer. Please help us. Best regards Dat Bui Located in Hanoi, Vietnam

hjjeon0608 · Answer

Hi, btiendat Your reset timing is correct. And there is information of reset timing at datasheet section 10.4 AC characteristic. But ping is another things. If you do ping test, W7100A must need link up. And phy negotiation takes some time and each time are different. So you need to check PHY status register(link up/down information). And reset doesn’t affect aging of W7100A. Best regards.

btiendat · Answer

Dear hjjeon0608, Thank you very much for your answer. Now we can be more sure when we reset W7100A. We appreciate very much Wiznet’s support. Dat Bui