Texas Instruments LaunchPad MSP-EXP430F5529LP User Manual page 55

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Q: I'm trying to power the LaunchPad from a USB power supply (not an actual USB host), and it is
not working. Does the LaunchPad not support this?
This problem is fixed in Rev1.5 and later LaunchPads. Unfortunately Rev1.4 does not. USB hubs typically
shouldn't enable power to their downstream devices until the hubs themselves enumerate on the host, and
that's what the TUSB2046 on the Rev1.4 F5529 LaunchPad does through the TPS2041B power switches.
If the hub never enumerates, power is not provided to the target F5529. Because the downstream device
is permanently attached in this application, the TPS2041B switches are not required by the USB
specification. Rev1.5 and newer F5529 LaunchPads have these switches removed, to avoid this problem.
Again, the benefit of the hub is single-cable development. Other power supplies can still be applied via the
power header.
Q: With the female headers on the bottom, the board does not sit flat on the table, and I can't
unsolder them. Why did TI do this?
A: For several reasons. A major feedback item on previous LaunchPads was the desire for female
headers instead of male ones. But simply using female instead is problematic, because compatibility with
existing BoosterPacks would be lost, and some people prefer male headers. So, adding female headers
without removing male ones satisfies both preferences. It also allows more flexibility in stacking
BoosterPacks and other LaunchPads.
The downside to this approach is perhaps that the board does not sit flat. But while a USB cable is
attached (the usual development model), it tends to not sit flat anyway.
For those wishing the board to sit flat, holes are drilled in the corners so that standoffs can be fastened.
Rubber bumper feet also should work.
SLAU533B – September 2013 – Revised June 2014
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MSP-EXP430F5529LP LaunchPad™ Development Kit User's Guide
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