Port b schematics – Rainbow Electronics AT90S8515 User Manual
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AT90S8515
0841G–09/01
• AIN0 – Port B, Bit 2
AIN0: Analog Comparator Positive Input. When configured as an input (DDB2 is cleared
[zero]) and with the internal MOS pull-up resistor switched off (PB2 is cleared [zero]),
this pin also serves as the positive input of the On-chip Analog Comparator.
• T1 – Port B, Bit 1
T1: Timer/Counter1 counter source. See the timer description for further details
• T0 – Port B, Bit 0
T0: Timer/Counter0 counter source. See the timer description for further details.
Port B Schematics
Note that all port pins are synchronized. The synchronization latches are, however, not
shown in the figures.
Figure 46. Port B Schematic Diagram (Pins PB0 and PB1)
DA
T
A
BUS
D
D
Q
Q
RESET
RESET
C
C
WD
WP
RD
MOS
PULL-
UP
PBn
R
R
WP:
WD:
RL:
RP:
RD:
WRITE PORTB
WRITE DDRB
READ PORTB LATCH
READ PORTB PIN
READ DDRB
DDBn
PORTBn
SENSE CONTROL
TIMERn CLOCK
SOURCE MUX
CSn2
CSn0
RL
RP
CSn1
n:
0,1