AT43USB325E-AC Atmel, AT43USB325E-AC Datasheet - Page 69

• 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

8.1.8
8.1.9
3355C–USB–4/05
Control Write Status Response State
Interrupt/Bulk IN Transfers at Function End-point
The Function Interface Unit receives an IN token from the Host. The FIU responds with a zero
length DATA1 packet, retrying until it receives an ACK back from the Host. The FIU then asserts
a TX_COMPLETE interrupt.
The firmware must first condition the end-point through the End-point Control Register, FEND-
P1/2/3_CNTR:
The Function Interface Unit receives an IN token from the Host. The FIU responds with NAKs
until TX_PACKET_READY is set. The FIU then sends the data in the FIFO upstream, retrying
u n t i l i t s u c c e s s f u l l y r e c e i v e s a n A C K f r o m t h e h o s t . F i n a l l y , t h e F I U c l e a r s t h e
TX_PACKET_READY bit and asserts a TX_COMPLETE interrupt.
1. Read UISR
2. Read FCSR1/2/3
3. Clear TX_COMPLETE
4. Set UIAR[FEP1/2/3 INTACK] to clear the interrupt source
1. IN token from Host
2. Send DATA1(0)
3. ACK from Host
4. Set TX Complete
Set end-point direction: set EPDIR
Set interrupt or bulk: EPTYPE = 11 or 10
Enable end-point: set EPEN
If more data: fill FIFO, set TX Packet Ready
Wait for TX_COMPLETE interrupt
If no more data: set DATA END in FCAR1/2/3
Hardware
INT
5. Read UISR
6. Read CSR0
7. Clear TX COMPLETE, clear Data
8. Set UIAR[EP0 INTACK] to clear
End, set Force STALL in CAR0
the interrupt source
Firmware
AT43USB325
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