The Embedded Debugger features an Atmel Data Gateway Interface (DGI) by using
either an SPI or I²C port. The DGI can be used to send a variety of data from the SAM R21
to the host PC.
Table 4-13. DGI Interface Connections When Using
SPI| Pin on SAM R21 | Function |
|---|
| PA27 | GPIO SPI SS (Slave select) (SAM R21 is Master) |
| PB02 | SERCOM5 PAD[0] SPI MISO (Master In, Slave Out) |
| PB22 | SERCOM5 PAD[2] SPI MOSI (Master Out, Slave in) |
| PB23 | SERCOM5 PAD[3] SPI SCK (Clock Out) |
Table 4-14. DGI Interface Connections When Using
I²C| Pin on SAM R21 | Function |
|---|
| PA16 | SERCOM1 PAD[0] I²C SDA (Data line) |
| PA17 | SERCOM1 PAD[1] I²C SCL (Clock line) |
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 R21 application code.
Table 4-15. GPIO Lines Connected to the
EDBG| Pin on SAM R21 | Function |
|---|
| PA08 | GPIO0 |
| PA09 | GPIO1 |
| PA12 | GPIO2 |
| PA14 | GPIO3 |
