User's Manual

8
AVR2042
8334A-AVR-11/10
Table 5-7. PORTE header connection.
Header PORTE ATxmega256A3
1 PE0 (62)
2 PE1 (63)
3 PE2 (64)
4 PE3 (1)
5 PE4 (2)
6 PE5 (3)
7
8
9 GND
10 VTG
Table 5-8. PORTF header connection.
Header PORTF ATxmega256A3
1 PF0 (62)
2 PF1 (63)
3 PF2 (64)
4 PF3 (1)
5 PF4 (2)
6 PF5 (3)
7 PF6 (4)
8 PF7 (5)
9 GND
10 VTG
5.5 Serial flash
The Atmel REB-CBB is populated with a 2MB serial flash device (Atmel AT25DF021)
for persistent data storage. It is capable of storing one complete firmware image of
the Atmel ATxmega256A3, which makes it suitable for over-the-air upgrades (OTA). It
is connected to SPID PD4..7.
Table 5-9. Serial flash connection.
ATxmega256A3 AT25DF021
PD4 (30) #CS
PD5 (31) SI
PD6 (32) SO
PD7 (33) SCK
The AT25DF021 supports SPI frequencies of up to 50MHz on supply voltages down
to 2.3V. When operating the board below 2.3V, the serial flash can not be accessed,
see datasheet [3] for
more information.