Nvidia DG-04927-001_V01 Manuel D’Utilisation

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Tegra 200 Series Developer Board User Guide
 
DG-04927-001_v01
 
Advance Information – Subject to Change 
25
 
 
NVIDIA CONFIDENTIAL
 
4.5.1  Force Recovery 
The Tegra 250 requires USB1 to be available as a Device for Force Recovery mode which is used to download new firmware.  
This is shown in Figure 12 where a USB Mini B connector is available to connect to a Host system.  Force Recovery mode is 
entered by keeping the FORCE_RECOVERY pin low when the system is first powered up (until SYS_RESET_N goes high.  
This is accomplished by pressing the momentary push button shown during power-on. 
Figure 12  Force Recovery Connections 
 
4.5.2  ULPI 
The Tegra 250 optionally supports ULPI (UMTI+ Low Pin Interface) as an option to connect to external USB PHYs, or other 
compatible devices. 
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12 bit interface including ULPI_CLK, ULPI_DIR, ULPI_NXT, ULPI_STP and ULPI_DAT[7:0] 
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Operates from 60 MHz clock 
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8-bit SDR data interface - 4-bit DDR data I/F not supported 
Figure 13 shows the Tegra 250 interfacing with an external ULPI-USB PHY.  The USB PHY can be used to interface to a 
compatible Baseband, a USB Hub, etc. 
Figure 13.  Example ULPI connection to External SMSC USB3317 USB PHY