
8
6384DS–ATARM–13-Jan-10
AT91SAM9G20 Summary
Timer/Counter - TCx
TCLKx
TC Channel x External Clock Input
Input
TIOAx
TC Channel x I/O Line A
I/O
TIOBx
TC Channel x I/O Line B
I/O
Serial Peripheral Interface - SPIx_
SPIx_MISO
Master In Slave Out
I/O
SPIx_MOSI
Master Out Slave In
I/O
SPIx_SPCK
SPI Serial Clock
I/O
SPIx_NPCS0
SPI Peripheral Chip Select 0
I/O
Low
SPIx_NPCS1-SPIx_NPCS3
SPI Peripheral Chip Select
Output
Low
Two-Wire Interface
TWD
Two-wire Serial Data
I/O
TWCK
Two-wire Serial Clock
I/O
USB Host Port
HDPA
USB Host Port A Data +
Analog
HDMA
USB Host Port A Data -
Analog
HDPB
USB Host Port B Data +
Analog
HDMB
USB Host Port B Data -
Analog
USB Device Port
DDM
USB Device Port Data -
Analog
DDP
USB Device Port Data +
Analog
Ethernet 10/100
ETXCK
Transmit Clock or Reference Clock
Input
MII only, REFCK in RMII
ERXCK
Receive Clock
Input
MII only
ETXEN
Transmit Enable
Output
ETX0-ETX3
Transmit Data
Output
ETX0-ETX1 only in RMII
ETXER
Transmit Coding Error
Output
MII only
ERXDV
Receive Data Valid
Input
RXDV in MII, CRSDV in RMII
ERX0-ERX3
Receive Data
Input
ERX0-ERX1 only in RMII
ERXER
Receive Error
Input
ECRS
Carrier Sense and Data Valid
Input
MII only
ECOL
Collision Detect
Input
MII only
EMDC
Management Data Clock
Output
EMDIO
Management Data Input/Output
I/O
Table 3-1.
Signal Description List (Continued)
Signal Name
Function
Type
Active
Level
Comments