The Embedded Debugger features an Atmel Data Gateway Interface
(DGI) by using either an SPI or TWI port. The DGI can be used to send a variety of data
from the ATmega256RFR2 to the host PC. For further information on how to use the DGI
interface, see Embedded Debugger.
Table 1. DGI Interface Connections
When Using SPI| Pin on ATmega256RFR2 |
Function |
|---|
| PB0 |
Slave select (ATmega256RFR2 is Master) |
| PB1 |
SPI SCK (Clock Out) |
| PB2 |
SPI MOSI (Master Out, Slave in) |
| PB3 |
SPI MISO (Master In, Slave Out) |
Table 2. DGI Interface Connections
When Using TWI| Pin on ATmega256RFR2 |
Function |
|---|
| PD0 |
SCL (Clock line) |
| PD1 |
SDA (Data 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 ATmega256RFR2 application code. For further information
on how to configure and use the GPIO monitoring features, see Embedded Debugger.
Table 3. GPIO Lines Connected To
the EDBG| Pin on ATmega256RFR2 |
Function |
|---|
| PE2 |
GPIO0 |
| PE3 |
GPIO1 |
| PE5 |
GPIO2 |
| PE6 |
GPIO3 |