AT91SAM7X128 Atmel, AT91SAM7X128 Datasheet - Page 453

• Manufacturer Part Number: AT91SAM7X128
• Description: MCU 32-Bit 91S ARM7TDMI RISC 128KB Flash 1.8V/3.3V 100-Pin LQFP
• Manufacturer: Atmel

Specifications of AT91SAM7X128

• Package: 100LQFP
• Device Core: ARM7TDMI
• Family Name: 91S
• Maximum Speed: 55 MHz
• Ram Size: 32 KB
• Program Memory Size: 128 KB
• Operating Supply Voltage: 1.8|3.3 V
• Data Bus Width: 32 Bit
• Program Memory Type: Flash
• Number Of Programmable I/os: 62
• Interface Type: CAN/Ethernet/SPI/I2S/TWI/USART/USB
• On-chip Adc: 8-chx10-bit
• Operating Temperature: -40 to 85 °C
• Number Of Timers: 3

34.5.1.2
34.5.1.3
6120H–ATARM–17-Feb-09
USB Bus Transactions
USB Transfer Event Definitions
Each transfer results in one or more transactions over the USB bus. There are three kinds of
transactions flowing across the bus in packets:
As indicated below, transfers are sequential events carried out on the USB bus.
Table 34-3.
Notes:
A status transaction is a special type of host-to-device transaction used only in a control transfer.
The control transfer must be performed using endpoints with no ping-pong attributes. According
to the control sequence (read or write), the USB device sends or receives a status transaction.
Control Transfers
Interrupt IN Transfer
(device toward host)
Interrupt OUT Transfer
(host toward device)
Isochronous IN Transfer
(device toward host)
Isochronous OUT Transfer
(host toward device)
Bulk IN Transfer
(device toward host)
Bulk OUT Transfer
(host toward device)
1. Setup Transaction
2. Data IN Transaction
3. Data OUT Transaction
1. Control transfer must use endpoints with no ping-pong attributes.
2. Isochronous transfers must use endpoints with ping-pong attributes.
3. Control transfers can be aborted using a stall handshake.
USB Transfer Events
(1) (3)
(2)
AT91SAM7X512/256/128 Preliminary
(2)
• Setup transaction > Data IN transactions > Status
• Setup transaction > Data OUT transactions > Status
• Setup transaction > Status IN transaction
• Data IN transaction > Data IN transaction
• Data OUT transaction > Data OUT transaction
• Data IN transaction > Data IN transaction
• Data OUT transaction > Data OUT transaction
• Data IN transaction > Data IN transaction
• Data OUT transaction > Data OUT transaction
OUT transaction
IN transaction
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