AT43USB325E-AU Atmel, AT43USB325E-AU Datasheet - Page 66

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

Specifications of AT43USB325E-AU

• 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: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 64-LQFP
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

8.1.3
66
AT43USB325
Setup Response State
The Function Interface Unit (FIU) receives a SETUP token with 8 bytes of data from the Host.
The FIU stores the data in the FIFO, sends an ACK back to the host and asserts an RX_SETUP
interrupt.
1. SETUP token, DATA from Host
2. ACK to Host
3. Store data in FIFO
4. Set RX SETUP
Hardware
INT
5. Read UISR
6. Read CSR0
7. Read Byte Count
8. Read FIFO
9. Parse command data
10. Write to H/FCAR0:
11. If Control Read: set DIR, clear RX
12. If Control Write: clear DIR in CAR0
13. If no Data Stage: set Data End,
14. Set UIAR[EP0 INTACK] to clear
SETUP, fill FIFO, set TX Packet
Ready in CAR0
clear DIR, set Force STALL in
CAR0
the interrupt source
Firmware
3355C–USB–4/05