i.MX25 SODIMM PC Loading bootloader

This page shows the steps how to initiate On-Chip Debugging and load bootloader into i.MX25 SODIMM PC - Development kit.

JTAG Debugger and Programmer Installation

• Connect JTAG Cable to USB port on a computer. JTAG device should be automatically recognized and prepared for usage.
• Download OpenOCD v0.6.0 software
• Unzip the files

Running Open On-Chip Debugger

Locate the folder where the software was unpacked. Run OpenOCD utility in command line (by using Total Commander or Windows Command Prompt):

openocd.exe -f vmx25w.cfg

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Debugging session is opened and running:
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Connecting to Open On-Chip Debugger session

Using Windows Telnet Client

Click on Start/Run (or press Windows key + R), and open the Telnet session using 4444 port:

telnet localhost 4444

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Telnet session is active and ready for use:
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Using terminal emulator

To open Telnet service using TeraTerm program, click on File/New Connection, select TCP/IP option and type 4444 into TCP port# field. The IP address to connect to is localhost (127.0.0.1):
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TeraTerm session is running and ready for use:
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Establishing serial connection

Open TeraTerm program, click on File/New Connection, choose Serial and select the port which was assigned to the serial console:
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A successful connection is created only if the following serial port settings are applied (115200, 8n1):
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Boot mode options

H902 jumper (BOOTMODE) allows to choose different bootloader sources:

• Direct boot is enabled when a link is placed between pins 1 and 2. This mode is chosen by default.
• Serial Boot (Internal boot) is selected when pins 2 and 3 are shortened.

Direct Boot	Serial Boot

Important: No boot mode changes are required during firmware loading.

Loading bootloader

The following commands need to be placed inside Localhost Telnet session and executed one by one. Console logs are included for comparison:

reset_halt

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vmx25_init

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boot

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Barebox was loaded into the i.MX25 SODIMM PC Module SRAM and executed:
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As this fresh Barebox is stored in SRAM only at this point, switching the module off causes the bootloader to be erased. To store the new Barebox and use it automatically after power on, image flashing is required. Follow this section to do so.