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TMS320C6421
Fixed-Point Digital Signal Processor
SPRS346B–JANUARY 2007–REVISED APRIL 2007
PLL Output Frequency
: (PLLOUT = CLKIN frequency * boot PLL Multiplier)
must
stay within the
PLLOUT frequency range in
Table 6-15
,
PLLC1 Clock Frequency Ranges
.
Device Frequency
: (SYSCLK1) calculated from
Table 3-5
must not
exceed the SYSCLK1 maximum
frequency in
Table 6-15
,
PLLC1 Clock Frequency Ranges
.
For example, for a 600-MHz device with a CLKIN = 25 MHz, in order to stay within the PLLOUT
frequency range and SYSCLK1 maximum frequency from
Table 6-15
,
PLLC1 Clock Frequency
Ranges
, the user
must
select a boot mode with a PLL1 multiplier between x16 and x24.
EMIFA Boot Modes
3.4.1.3
As shown in
Table 3-4
and
Table 3-5
, there are different types of EMIFA Boot Modes. This subsection
summarizes these types of EMIFA boot modes. For further detailed information, see the
Using the
TMS320C642x Bootloader
Application Report (literature number SPRAAK5).
EMIFA ROM Direct Boot in PLL Bypass Mode
(FASTBOOT = 0, BOOTMODE[3:0] = 0100b)
–
The C64x+ fetches the code directly from EMIFA Chip Select 2 Space [EM_CS2] (address
0x42000000)
–
The PLL is in Bypass Mode
–
EMIFA is configured as Asynchronous EMIF. The user is responsible for ensuring the desirable
Asynchronous EMIF pins are available through configuration pins AEM[2:0]. AEM[2:0]
must
be
configured to 010b [EMIFA (Async) Pinout Mode 2].
EMIFA ROM Fastboot with AIS
(FASTBOOT = 1, BOOTMODE[3:0] = 0100b)
–
The C64x+ begins execution from the internal bootloader ROM at address 0x00100000.
–
The bootloader code programs PLLC1 to PLL Mode to speed up the boot process. The PLL
multiplier value is determined by the PLLMS[2:0] configuration as shown in
Table 3-5
.
–
The bootloader code reads code from the EMIFA EM_CS2 space using the application image script
(AIS) format.
–
EMIFA is configured as Asynchronous EMIF. The user is responsible for ensuring the desirable
Asynchronous EMIF pins are available through configuration pins AEM[2:0]. AEM[2:0]
must
be
configured to 010b [EMIFA (Async) Pinout Mode 2].
EMIFA ROM Fastboot without AIS
: (FASTBOOT = 1, BOOTMODE[3:0] = 1001b)
–
The C64x+ begins execution from the internal bootloader ROM at address 0x00100000.
–
The bootloader code programs PLLC1 to PLL Mode to speed up the boot process. The PLL
multiplier value is determined by the PLLMS[2:0] configuration as shown in
Table 3-5
.
–
The bootloader code then jumps to the EMIFA EM_CS2 space, at which point the C64x+ fetches
the code directly from address 0x42000000.
–
EMIFA is configured as Asynchronous EMIF. The user is responsible for ensuring the desirable
Asynchronous EMIF pins are available through configuration pins AEM[2:0]. AEM[2:0]
must
be
configured to 010b [EMIFA (Async) Pinout Mode 2].
NAND Flash Boot
: (FASTBOOT = 0 or 1, BOOTMODE[3:0] = 0111b)
–
The C64x+ begins execution from the internal bootloader ROM at address 0x00100000.
–
Depending on the FASTBOOT and PLLMS[2:0] settings, the bootloader code may program the
PLLC1 to PLL Mode to speed up the boot process. See
Table 3-4
and
Table 3-5
.
–
The bootloader code reads the code from EMIFA (NAND) EM_CS2 (address 0x42000000) using
AIS format.
–
EMIFA is configured in NAND mode. The user is responsible for ensuring the desirable
Asynchronous EMIF pins are available through configuration pins AEM[2:0]. AEM[2:0]
can
be
configured to 010b [EMIFA (Async) Pinout Mode 2] or 101b [EMIFA (NAND) Pinout Mode 5].
3.4.1.4
Serial Boot Modes (I2C, UART[UART0], SPI[McBSP0])
This subsection discusses how the bootloader configures the clock dividers for the serial boot modes—I2C
boot, UART boot, and SPI boot.
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Device Configurations
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