AT90USB64/128
ALE is the external data memory Address latch enable.
HWB allows to execute the bootloader section after reset when tied to ground during external
reset pulse. The HWB mode of this pin is active only when the HWBE fuse is enable.
• RD – Port E, Bit 1
RD is the external data memory read control enable.
• WR – Port E, Bit 0
WR is the external data memory write control enable.
Table 10-16. Overriding Signals for Alternate Functions PE7..PE4
PE7/INT7/AIN.1/
UVCON
PE5/INT5/
TOSC1
PE4/INT4/
TOSC2
Signal
Name
PE6/INT6/AIN.0
PUOE
PUOV
DDOE
DDOV
PVOE
PVOV
DIEOE
DIEOV
DI
0
0
0
0
0
0
0
0
UVCONE
UVCONE
UVCONE
UVCON
INT7 ENABLE
1
0
0
0
0
0
0
0
0
0
0
0
0
INT6 ENABLE
1
INT5 ENABLE
INT4 ENABLE
1
1
INT7 INPUT
AIN1 INPUT
INT6 INPUT
AIN0 INPUT
INT5 INPUT
–
INT4 INPUT
–
AIO
Table 10-17. Overriding Signals for Alternate Functions in PE3..PE0
Signal
Name
PUOE
PUOV
DDOE
DDOV
PVOE
PVOV
DIEOE
DIEOV
DI
PE3/UID
PE2/ALE/HWB
PE1/RD
PE0/WR
UIDE
0
SRE
0
SRE
0
1
0
UIDE
SRE
1
SRE
1
SRE
0
0
0
SRE
ALE
0
SRE
RD
0
SRE
WR
0
0
UIDE
1
0
0
1
UID
0
HWB
0
–
–
PE0
0
0
AIO
–
–
–
–
89
7593A–AVR–02/06
ATMEL [ ATMEL ]
