TMS320DM6433 Datasheet, PDF (75/271 Pages) Texas Instruments – Digital Media Processor

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TMS320DM6433
Digital Media Processor
SPRS343C – NOVEMBER 2006 – REVISED JUNE 2008
3.4 Boot Sequence
The boot sequence is a process by which the device's memory is loaded with program and data sections,
and by which some of the device's internal registers are programmed with predetermined values. The boot
sequence is started automatically after each device-level global reset. For more details on device-level
global resets, see Section 6.5, Reset.
There are several methods by which the memory and register initialization can take place. Each of these
methods is referred to as a boot mode. The boot mode to be used is selected at reset. For more
information on the bootmode selections, see Section 3.4.1, Boot Modes.
The device is booted through multiple means—primary bootloaders within internal ROM or EMIFA, and
secondary user bootloaders from peripherals or external memories. Boot modes, pin configurations, and
register configurations required for booting the device, are described in the following subsections.
3.4.1 Boot Modes
The DM6433 boot modes are determined by these device boot and configuration pins. For information on
how these pins are sampled at device reset, see Section 6.5.1.2, Latching Boot and Configuration Pins.
• BOOTMODE[3:0]
• PCIEN
• FASTBOOT
• AEM[2:0]
• PLLMS[2:0]
Note: The PLLMS[2:0] configuration pins are actually multiplexed with the AEAW[2:0] configuration pins.
For more details on the multiplexed AEAW[2:0]/PLLMS[2:0] configuration pins and control, see
Section 3.5.1.2, EMIFA Address Width Selects (AEAW[2:0]) and FASTBOOT PLL Multiplier Selects
(PLLMS[2:0]).
BOOTMODE[3:0] and PCIEN determine the type of boot (e.g., I2C Boot, EMIFA Boot, HPI Boot, or PCI
Boot, etc.). FASTBOOT determines if the PLL is enabled during boot to speed up the boot process.
The combination of AEM[2:0] and PLLMS[2:0] is used by bootloader code to determine the PLL multiplier
used during fastboot modes (FASTBOOT = 1).
The DM6433 boot modes are grouped into three categories—Non-Fastboot Modes, Fixed-Multiplier
Fastboot Modes, and User-Select Multiplier Fastboot Modes.
• Non-Fastboot Modes (FASTBOOT = 0): The device operates in default PLL bypass mode during
boot. The Non-Fastboot bootmodes available on the DM6433 are shown in Table 3-5.
• Fixed-Multiplier Fastboot Modes (FASTBOOT = 1, AEM[2:0] = 001b): The bootloader code speeds
up the device during boot according to the fixed PLL multipliers. The Fixed-Multiplier Fastboot
bootmodes available on the DM6433 are shown in Table 3-6.
Note: The PLLMS[2:0] configurations have no effect on the Fixed-Multiplier Fastboot Modes, as these
pins function as AEAW[2:0] to select the EMIFA address width when AEM[2:0] = 001b.
• User-Select Multiplier Fastboot Modes (FASTBOOT = 1, AEM[2:0] = 000b,011b,100b,101b): The
bootloader code speeds up the device during boot. The PLL multiplier is selected by the user via the
PLLMS[2:0] pins. The User-Select Multiplier Fastboot bootmodes available on the DM6433 are shown
in Table 3-7.
All other modes not shown in these tables are reserved and invalid settings.
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Device Configurations
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