AT91RM9200-QI-002 Atmel, AT91RM9200-QI-002 Datasheet - Page 83

• Manufacturer Part Number: AT91RM9200-QI-002
• Description: IC ARM9 MCU 208 PQFP
• Manufacturer: Atmel
• Series: AT91SAMr

Specifications of AT91RM9200-QI-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: 208-MQFP, 208-PQFP
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Eeprom Size: -
• Data Converters: -

13. Boot Program
13.1
1768I–ATARM–09-Jul-09
Overview
The Boot Program is capable of downloading an application in an AT91RM9200-based system.
It integrates a Bootloader and a boot Uploader to assure correct information download.
The Bootloader is activated first. It looks for a sequence of eight valid ARM exception vectors in
a DataFlash connected to the SPI, an EEPROM connected to the Two-wire Interface (TWI) or
an 8-bit memory device connected to the external bus interface (EBI). All these vectors must be
Bbranch or LDR load register instructions except for the sixth instruction. This vector is used to
store information, such as the size of the image to download and the type of DataFlash device.
If a valid sequence is found, code is downloaded into the internal SRAM. This is followed by a
remap and a jump to the first address of the SRAM.
If no valid ARM vector sequence is found, the boot Uploader is started. It initializes the Debug
Unit serial port (DBGU) and the USB Device Port. It then waits for any transaction and down-
loads a piece of code into the internal SRAM via a Device Firmware Upgrade (DFU) protocol for
USB and XMODEM protocol for the DBGU. After the end of the download, it branches to the
application entry point at the first address of the SRAM.
The main features of the Boot Program are:
• Default Boot Program stored in ROM-based products
• Downloads and runs an application from external storage media into internal SRAM
• Downloaded code size depends on embedded SRAM size
• Automatic detection of valid application
• Bootloader supporting a wide range of non-volatile memories
• Boot Uploader in case no valid program is detected in external NVM and supporting several
• Serial communication on a DBGU (XModem protocol)
• USB Device Port (DFU Protocol)
communication media
– SPI DataFlash connected on SPI NPCS0
– Two-wire EEPROM
– 8-bit parallel memories on NCS0
AT91RM9200
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