Table 4-1. IO Pin Functions for PORTxCFG=0 and PORTxCFG=1
PORTxCFG
PORTxCFG bit = 1
bit = 0
Signal
PA0
PA1
PA2
PA3
PA4
PA5
PA6
PA7
PB0
PB1
PB2
PB3
PB4
PB5
PB6
PB7
PC0
PC1
PC2
PC3
PC4
PC5
PC6
PC7
Signal
T0OUT
T1OUT
OE#
Direction
OUT
OUT
OUT
OUT
OUT
OUT
OUT
OUT
IN
Description
Timer 0 Overflow Pulse
Timer 1 Overflow Pulse
EZ-USB Output Enable
EZ-USB Chip Select
EZ-USB Fast Write Strobe
EZ-USB Fast Read Strobe
UART0 Mode 0 Data Out
UART1 Mode 0 Data Out
Timer 2 Clock Input
Timer 2 Capture/Reload
UART1 Receive Data
UART1 Transmit Data
Interrupt 4
Figure
4-2
4-2
4-2
4-2
4-2
4-2
4-2
4-2
4-3
4-3
4-3
4-2
4-3
4-3
4-3
4-2
4-3
4-2
4-3
4-3
4-3
4-3
4-2
4-2
CS#
FWR#
FRD#
RxD0OUT
RxD1OUT
T2
T2EX
RxD1
TxD1
INT4
IN
IN
OUT
IN
INT5
IN
Interrupt 5
INT6
IN
Interrupt 6
T2OUT
RxD0
TxD0
INT0#
INT1#
T0
OUT
IN
Timer 2 Overflow Pulse
UART0 Receive Data
UART0 Transmit Data
Interrupt 0
OUT
IN
IN
Interrupt 1
IN
Timer 0 Clock Input
Timer 1 Clock Input
Write Strobe
T1
IN
WR#
OUT
OUT
RD#
Read Strobe
Depending on whether the alternate function is an input or output, the IO logic is slightly
different, as shown in Figure 4-2 (output) and Figure 4-3 (input). The last column of
Table 4-1 indicates which figure applies to each pin.
EZ-USB TRM v1.9
Chapter 4. EZ-USB CPU
Page 4-3
CYPRESS [ CYPRESS ]
