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5
Device Configurations and Initialization
5.1
Device Reset
5.2
Device Configuration
Device Configurations and Initialization
Table 3. Pin and Package Differences
Device
Package Type (s)
Pin Count
TCI100
GLZ Ball Grid Array (BGA) 0.8mm pitch,
532
23 x 23 mm
TCI6482
ZTZ Ball Grid Array (BGA) 0.8mm pitch,
697
24 x 24 mm
On the TCI6482 device, bootmode and certain device configuration/peripheral selections are determined
at device reset, while peripheral usage (enabled/disabled) is determined by the Peripheral Configuration
registers after the device reset. The peripherals on the TCI6482 device are “disabled” and need to be
“enabled”. This is different than the TCI100 in which case the peripherals selected by the boot strap
options were enabled on power-up. The basic information on configuration options, boot modes options
and use of the Power Configuration registers can be found in the TCI6482 data manual.
There are several ways to reset the TCI6482 and these are described in the TCI6482 data manual. The
two external resets, POR and RESET, need to be driven to a valid logic level at all times. POR must be
asserted (low) on a power-up while the clocks and power planes become stable. RESET can be used
from the powered up state to issue a warm reset, which performs the same as a POR except that test and
emulation logic are not reset. If a warm reset is not needed, RESET can be pulled up to DVDD33.
In revision 1.1 silicon, when POR is held low the internal pull-up and pull-down resistors are disabled. This
requires the use of external pull-up and pull-down resistors for all pins that have their states latched by
POR. Alternatively, after POR is de-asserted long enough for the internal resistors to pull voltage levels to
valid states (> 100uS) bringing RESET low for at least 24 CLKIN1 cycles and then high again will allow
re-latching the state of the configuration strapping with valid values from the internal pull-ups, pull-downs.
While POR is low, large currents may be seen on the DVDD33 power plane due to floating inputs (i.e. the
EMIF bus). If the user wishes to avoid these currents external pull-ups or pull-downs should be used.
Refer to the TCI6482 Silicon Errata document for complete details. In revision 2.0 silicon and later the
internal pull-up and pull-down resistors will not be disabled under any conditions.
The RESETSTATz signal indicates the internal reset state. The RESETSTATz is asserted (low) on a
power-on reset, warm reset, max reset, or system reset. The only reset that does not cause
RESETSTATz to be asserted is a CPU reset (issued from the PCI peripheral).
The TCI6482 device configuration options are multiplexed on the EMIFA address AEA[19:0] and EMIFA
bank address lines ABA[1:0]. There is one dedicated configuration pin, PCI_EN. Refer to the TCI6482
data manual for details on the configuration options. All reset strapping pins have internal pull-ups or
pull-downs in the range of 30K ohms. If the EMIFA bus is not used the internal pull-ups and pull-downs
can be used and an external pull-up/down is only needed if the opposite setting is desired. If the
configuration pins are routed out from the device, the internal pullup/pulldown resistor should not be relied
upon; 1K pull-ups and pull-downs are recommended for all desired settings.
The core clock PLL multiplier is not set by reset configuration strapping as it was on the TCI100. The PLL
multiplier can only be set by CPU register writes. The registers are not accessible through boot
peripherals. The core clock speed when accessing the internal ROM must be not more than 750MHz. PCI
and Serial RapidIO boot modes automatically change the PLL multiplier to 15X, so the CLKIN1 must be
no more than 50MHz. For other boot modes it is suggested to set the multiplier early in the boot process
in order to reduce boot times. For details on setting the CLKIN1 PLL multiplier and divider settings refer to
section 6.1 and the TMS320TCI648x DSP PLL Controller Reference Guide (SPRU806).
TMS320TCI6482 Design Guide and Migration from TMS320TCI100
6
SPRAAC7B – April 2006
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