Circuit Design

Solder mask Layer in Eagle is defined as 29 tstop for top layer and 30 bstop for bottom layer. So you can check if you solder mask is as you required by display these two layers. The vias in Eagle are not cover with solder mask by default. You can change the default setting by changing the Design rules. Run Command: DRC; You will see the DRC check dialog. Select Masks tab. You can see the Limit option. The default value is 0 mm. Thus for all the vias it will not cover by solder mask. You change it to the value is bigger than the size of the via you want to cover with solder mask. Then you can run the command: display tstop or display bstop to check if it work as you want.

When I trying to debug the circuit board which designed for digital power using XMC1302T38-0032. I meet such error. “ Connecting to target...ERROR: Could not connect to target. Target connection failed. GDBServer will be closed...Restoring target state and closing J-Link connection... ” Finically I found the problem is because BMI (Boot Mode Index) is not right for debug. When XMC1000 device is just out of the factory, its default BMI value is ASC Bootstrap Load Mode. So I change the BMI to User Mode (debug) SWD0 (SWDIO=P0.14, SWDCLK=P0.15). The I can sue DAVE4 to debug the boards. I use the XMC42_OBD build in on XMC1000 boot kit to debug my board. The method to change BMI is. 1) click the tool icon as below.   2) On the pop up window, you can get or set BMI as below. 3) Set the BMI So I suggest before design your own board, try to under stand the BMI options first. Thus, you could design a board could use.