AT43USB326-AC Atmel, AT43USB326-AC Datasheet - Page 18

• Manufacturer Part Number: AT43USB326-AC
• Description: IC USB KEYBOARD CTRLR HUB 48LQFP
• Manufacturer: Atmel
• Series: AVR®r

Specifications of AT43USB326-AC

• Applications: Keyboard Controller
• Core Processor: AVR
• Program Memory Type: Mask ROM (16 kB)
• Controller Series: AT43USB
• Ram Size: 512 x 8
• Interface: USB
• Number Of I /o: 32
• Voltage - Supply: 4.4 V ~ 5.25 V
• Operating Temperature: 0°C ~ 70°C
• Mounting Type: Surface Mount
• Package / Case: 48-LQFP
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

Reset and
Interrupt Handling
18
AT43USB326
Figure 4. Oscillator and PLL
The AT43USB326 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 reg-
ister 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 Table 6. The list also determines
the 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 Inter-
rupt, etc.
Table 6. Reset and Interrupt Vectors
Vector No.
13
1
2
8
Program Address
$000
$002
$00E
$018
6.000 MHz
0.22 UF
Y1
C1
100
R1
Source
RESET
INT0
TIMER0, OVF
USB HW
0.01 UF
C2
U1
LFT
XTAL1
XTAL2
AT43USB326
Interrupt Definition
External Reset, Power-on Reset and
Watchdog Reset
USB Suspend and Resume
Timer/Counter0 Overflow
USB Hardware
3313D–USB–04/06