EP9312-CBZ Cirrus Logic Inc, EP9312-CBZ Datasheet - Page 120

• Manufacturer Part Number: EP9312-CBZ
• Description: IC ARM9 SOC UNIVERSAL 352PBGA
• Manufacturer: Cirrus Logic Inc
• Series: EP9r

Specifications of EP9312-CBZ

• Core Size: 16/32-Bit
• Core Processor: ARM9
• Speed: 200MHz
• Connectivity: EBI/EMI, EIDE, Ethernet, I²C, IrDA, Keypad/Touchscreen, SPI, UART/USART, USB
• Peripherals: AC'97, DMA, I&sup2:S, LCD, LED, MaverickKey, POR, PWM, WDT
• Number Of I /o: 16
• Program Memory Type: ROMless
• Ram Size: 32K x 8
• Voltage - Supply (vcc/vdd): 1.65 V ~ 3.6 V
• Data Converters: A/D 8x12b
• Oscillator Type: External
• Operating Temperature: 0°C ~ 70°C
• Package / Case: 352-BGA
• Controller Family/series: (ARM9)
• No. Of I/o's: 16
• Ram Memory Size: 16MB
• Cpu Speed: 200MHz
• No. Of Timers: 4
• No. Of Pwm Channels: 2
• Digital Ic Case Style: BGA
• Embedded Interface Type: AC97, I2S, SPI, UART, USB
• Rohs Compliant: Yes
• Processor Series: EP93xx
• Core: ARM920T
• Data Bus Width: 32 bit
• 3rd Party Development Tools: MDK-ARM, RL-ARM, ULINK2
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -
• Program Memory Size: -
• Lead Free Status / Rohs Status: Details
• Other names: 598-1258

4
4-2
Boot ROM
EP93xx User’s Guide
4.1.2.1 Image Header
4.1.2.2 Boot Algorithm
Note that the code retrieved via UART1 and the SPI Serial Flash is not intended to be a
complete operating system image. It is intended to be a small (up to 2 kbyte) loader that will,
in turn, retrieve a complete operating system image. This small loader can retrieve this
complete image through UART1 or the SPI Serial Flash (just as the Boot ROM did) or it can
be more sophisticated and retrieve it through the IrDA, USB, or Ethernet interfaces.
The Boot ROM code disables the ARM920T’s MMU, so any loader program that is
downloaded sees physical addresses. The loader is free to initialize the page tables and start
the MMU and caches if needed.
The Boot ROM code also does not enable interrupts or timers, so that the system delivered to
the user is in a known safe state and is ready for an operating system or for user code to be
loaded.
For images copied from the SPI Serial Flash or external FLASH, one of the ASCII strings,
“CRUS” or “SURC”, must be present as a HeaderID prefixed to an executable image.
The steps in the software boot process are:
1. Remap memory
2. Turn the green LED off and the red LED on
3. Disable the Watchdog timer
4. Read the Boot State
5. Set up the Clocks to run from external clocks (PLLs are not configured)
6. Based on the Boot State memory width, follow steps A, B, and C.
7. Based on the contents of the SysCfg register, start serial download (see
then follow Steps A, B, C, D, E, and F.
A. Initialize the SYNC Flash and SMC memory interfaces for slow (maximum
B. Initialize the SDRAM interfaces.
C. Perform minimal memory tests
A. Initialize UART1 to 9600 baud, 8 bits, no parity, 1 stop bit
B. Output a “<” character
C. Read 2048 (decimal count) characters from UART1 and store these in the internal
D. Output a “>” to signify 2048 characters have been read
E. Turn on Green LED
F. Jump to the start of the internal Boot Buffer
compatibility) operation
Boot buffer (alias for the Ethernet Mac buffer)
Copyright 2007 Cirrus Logic
Figure
4-1), and
DS785UM1