AT91RM9200-CI-002 Atmel, AT91RM9200-CI-002 Datasheet - Page 559

• Manufacturer Part Number: AT91RM9200-CI-002
• Description: IC ARM9 MCU 256 BGA
• Manufacturer: Atmel
• Series: AT91SAMr

Specifications of AT91RM9200-CI-002

• Core Processor: ARM9
• Core Size: 16/32-Bit
• Speed: 180MHz
• Connectivity: EBI/EMI, Ethernet, I²C, MMC, SPI, SSC, UART/USART, USB
• Peripherals: POR
• Number Of I /o: 122
• Program Memory Size: 128KB (128K x 8)
• Program Memory Type: ROM
• Ram Size: 48K x 8
• Voltage - Supply (vcc/vdd): 1.65 V ~ 1.95 V
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 256-BGA
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Eeprom Size: -
• Data Converters: -

34.5.2
34.5.2.1
Figure 34-4. Setup Transaction Followed by a Data OUT Transaction
34.5.2.2
1768I–ATARM–09-Jul-09
Using Endpoints Without Ping-pong Attributes
USB
Bus Packets
RXSETUP Flag
RX_Data_BKO
(USB_CSRx)
FIFO (DPR)
Content
Handling Transactions with USB V2.0 Device Peripheral
Setup Transaction
Data IN Transaction
Setup
PID
Setup Received
Setup is a special type of host-to-device transaction used during control transfers. Control trans-
fers must be performed using endpoints with no ping-pong attributes. A setup transaction needs
to be handled as soon as possible by the firmware. It is used to transmit requests from the host
to the device. These requests are then handled by the USB device and may require more argu-
ments. The arguments are sent to the device by a Data OUT transaction which follows the setup
transaction. These requests may also return data. The data is carried out to the host by the next
Data IN transaction which follows the setup transaction. A status transaction ends the control
transfer.
When a setup transfer is received by the USB endpoint:
Thus, firmware must detect the RXSETUP polling the UDP_CSRx or catching an interrupt, read
the setup packet in the FIFO, then clear the RXSETUP. RXSETUP cannot be cleared before the
setup packet has been read in the FIFO. Otherwise, the USB device would accept the next Data
OUT transfer and overwrite the setup packet in the FIFO.
Data IN transactions are used in control, isochronous, bulk and interrupt transfers and conduct
the transfer of data from the device to the host. Data IN transactions in isochronous transfer
must be done using endpoints with ping-pong attributes.
To perform a Data IN transaction, using a non ping-pong endpoint:
XX
• The USB device automatically acknowledges the setup packet
• RXSETUP is set in the UDP_CSRx register
• An endpoint interrupt is generated while the RXSETUP is not cleared. This interrupt is
carried out to the microcontroller if interrupts are enabled for this endpoint.
Data Setup
Set by USB Device
ACK
PID
Setup Handled by Firmware
Data OUT
PID
Interrupt Pending
Data Setup
Data OUT
Cleared by Firmware
NAK
PID
Data OUT
PID
Data Out Received
Set by USB
Device Peripheral
XX
Data OUT
AT91RM9200
ACK
PID
Data
OUT
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