DS2703K Maxim Integrated, DS2703K Datasheet - Page 8

• Manufacturer Part Number: DS2703K
• Description: Battery Management
• Manufacturer: Maxim Integrated
• Series: DS2703r

DS2703EVKIT
The software will also perform the SHA-1 calculations based on the Secret, ROM ID (if desired) and
Challenge text box values and compare its results to the results read back from the DS2703. If the MAC
computed by the software and MAC read back from the DS2703 match, then the software will display
“Verified”. If they do not match, “Not Verified” will be displayed. The user can view the Software
Computed MAC by using the Tools Menu – Show Software Computed MAC. The user also can compute
the MAC with the DS2703, then change 1 bit in one of the text boxes of the Secret, and then Compute the
MAC with software to see how big of a difference changing 1 bit will make.
If the MAC is “Not Verified”, make sure that the Challenge was written prior to computing the MAC. If
the “Not Verified” error continues, perhaps the Secret in the device does not match what is in the Secret
text boxes and the user will need to Load a Secret into the DS2703.
1-Wire COMMANDS
1 Wire Reset
All communication to the DS2703 occurs over the 1-Wire bus, but the device can be configured to
communicate at Regular 1-Wire Speed or at Over Drive Speed. The user can left-click on the 1-Wire
Reset button and a 1-Wire Reset will be generated at the proper 1-Wire speed. The caption below the 1-
Wire Reset button will display which 1-Wire Speed is used. It will also indicate whether a device on the
bus responded to the 1-Wire Reset with a Presence Detect pulse at the proper 1-Wire speed.
Read ROM
The user can left-click on the Read ROM button to perform the Read ROM function. The result of the
Read ROM will be displayed in the caption below the button. If a single 1-Wire device is located on the
bus, the device’s ROM ID will be displayed. If more than one 1-Wire device is on the bus, the result will
be a logical AND of the ROM ID’s of all of the devices on the bus. The result will also be displayed in
the ROM ID text boxes in the SHA-1 Commands Sections.
Search ROM
If one or more 1-Wire devices are on the bus, the user can left-click on the Search ROM button to
perform the Search ROM Routine. This will find all 1-Wire devices on the 1-Wire bus communicating at
the specified 1-Wire speed and will display the results in the list box. The user can left-click on any of
the ROM ID’s in the text box to select that device. The selected ROM will appear in the caption below
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