4.3.3 Atmel Data Gateway Interface
The Embedded Debugger features an Atmel Data Gateway Interface (DGI) by using either a SPI or I²C. The DGI can be used to send a variety of data from the ATSAML21J18B to the host PC. For further information on how to use the DGI interface, see Atmel Data Visualizer and the EDBG User Guide.
| SAM L21 pin | Function | Shared functionality |
|---|---|---|
| PB31 | GPIO/SPI SS (Slave select) (SAM L21 is Master) | - |
| PB16 | SERCOM5 PAD[0] SPI MISO (Master In, Slave Out) | EXT2 and EXT3 |
| PB22 | SERCOM5 PAD[2] SPI MOSI (Master Out, Slave in) | EXT2 and EXT3 |
| PB23 | SERCOM5 PAD[3] SPI SCK (Clock Out) | EXT2 and EXT3 |
| SAM L21 pin | Function | Shared functionality |
|---|---|---|
| PA08 | SERCOM2 PAD[0] SDA (Data line) | EXT1, EXT2, and EXT3 |
| PA09 | SERCOM2 PAD[1] SCL (Clock line) | EXT1, EXT2, and EXT3 |
Four GPIO lines are connected to the Embedded Debugger. The EDBG can monitor these lines and time stamp pin value changes. This makes it possible to accurately time stamp events in the SAM L21 application code. For further information on how to configure and use the GPIO monitoring features, see Atmel Data Visualizer and the EDBG User Guide.