AT91SAM7S256D-AU Atmel, AT91SAM7S256D-AU Datasheet - Page 148

• Manufacturer Part Number: AT91SAM7S256D-AU
• Description: ARM Microcontrollers - MCU 256K Flash SRAM 64K ARM based MCU
• Manufacturer: Atmel
• Series: SAM7S256r

Specifications of AT91SAM7S256D-AU

• Rohs: yes
• Core: ARM
• Processor Series: AT91SAM
• Data Bus Width: 16 bit/32 bit
• Maximum Clock Frequency: 55 MHz
• Program Memory Size: 256 KB
• Data Ram Size: 64 KB
• On-chip Adc: Yes
• Operating Supply Voltage: 3 V to 3.6 V
• Operating Temperature Range: - 40 C to + 85 C
• Package / Case: LQFP-64
• Mounting Style: SMD/SMT
• Interface Type: 2-Wire, I2S, SPI, USART
• Length: 7 mm

21.5.3.1
21.5.3.2
The device uses the USB communication device class (CDC) drivers to take advantage of the installed PC RS-232
software to talk over the USB. The CDC class is implemented in all releases of Windows
WindowsXP. The CDC document, available at www.usb.org, describes a way to implement devices such as ISDN
modems and virtual COM ports.
The Vendor ID is Atmel’s vendor ID 0x03EB. The product ID is 0x6124. These references are used by the host
operating system to mount the correct driver. On Windows systems, the INF files contain the correspondence
between vendor ID and product ID.
The USB protocol is a master/slave protocol. This is the host that starts the enumeration sending requests to the
device through the control endpoint. The device handles standard requests as defined in the USB Specification.
Table 21-2.
The device also handles some class requests defined in the CDC class.
Table 21-3.
Unhandled requests are STALLed.
There are two communication endpoints and endpoint 0 is used for the enumeration process. Endpoint 1 is a 64-
byte Bulk OUT endpoint and endpoint 2 is a 64-byte Bulk IN endpoint. SAM-BA Boot commands are sent by the
host through the endpoint 1. If required, the message is split by the host into several data payloads by the host
driver.
If the command requires a response, the host can send IN transactions to pick up the response.
Request
GET_DESCRIPTOR
SET_ADDRESS
SET_CONFIGURATION
GET_CONFIGURATION
GET_STATUS
SET_FEATURE
CLEAR_FEATURE
Request
SET_LINE_CODING
GET_LINE_CODING
SET_CONTROL_LINE_STATE
Enumeration Process
Communication Endpoints
Handled Standard Requests
Handled Class Requests
Definition
Returns the current device configuration value.
Sets the device address for all future device access.
Sets the device configuration.
Returns the current device configuration value.
Returns status for the specified recipient.
Used to set or enable a specific feature.
Used to clear or disable a specific feature.
Definition
Configures DTE rate, stop bits, parity and number of
character bits.
Requests current DTE rate, stop bits, parity and number
of character bits.
RS-232 signal used to tell the DCE device the DTE
device is now present.
SAM7S Series [DATASHEET]
®
6175M–ATARM–26-Oct-12
, from Windows98SE to
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