AT43USB325E-AC Atmel, AT43USB325E-AC Datasheet - Page 21

• Manufacturer Part Number: AT43USB325E-AC
• Description: IC USB KEYBOARD CTRLR HUB 64LQFP
• Manufacturer: Atmel
• Series: AVR®r

Specifications of AT43USB325E-AC

• Applications: Keyboard Controller
• Core Processor: AVR
• Program Memory Type: SRAM (16 kB)
• Controller Series: AT43USB
• Ram Size: 512 x 8
• Interface: SPI, 3-Wire Serial
• Number Of I /o: 42
• Voltage - Supply: 4.4 V ~ 5.25 V
• Operating Temperature: 0°C ~ 70°C
• Mounting Type: Surface Mount
• Package / Case: 64-LQFP
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

4.4
3355C–USB–4/05
Reset and Interrupt Handling
Figure 4-1.
The AT43USB325 provides 12 different interrupt sources with 4 separate reset vectors, each
with a separate program vector in the program memory space. Nine of the interrupt sources
share 2 interrupt reset vectors. These nine are the USB related interrupts. All interrupts are
assigned individual enable bits which must be set (one) together with the I-bit in the status regis-
ter in order to enable the interrupt.
The lowest addresses in the program memory space are automatically defined as the Reset and
Interrupt vectors. The complete list of vectors is shown in
priority levels of the different interrupts. The lower the address, the higher is the priority level.
RESET has the highest priority, and next is INT0 – the USB Suspend and Resume Interrupt, etc.
Table 4-1.
Vector No.
13
1
2
3
4
5
6
7
8
Program Address
$000
$002
$004
$006
$008
$00A
$00C
$00E
$018
Oscillator and PLL
Reset and Interrupt Vectors
6.000 MHz
0.22 UF
Y1
C1
100
R1
Source
RESET
INT0
INT1
TIMER1 CAPT
TIMER1 COMPA
TIMER1 COMPB
TIMER1, OVF
TIMER0, OVF
USB HW
0.01 UF
C2
U1
LFT
XTAL1
XTAL2
AT43USB325
Interrupt Definition
External Reset, Power-on Reset and
Watchdog Reset
USB Suspend and Resume
External Interrupt Request 1
Timer/Counter1 Capture Event
Timer/Counter1 Compare Match A
Timer/Counter1 Compare Match B
Timer/Counter1 Overflow
Timer/Counter0 Overflow
USB Hardware
Table
4-1. The list also determines the
AT43USB325
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