Major Credit to SDX's FTEN for being first with his very original idea and micro Usb version of this hardware mod. If it weren't for him, I would not have dared to do this.
See his original thread: Self Powered USB Host on the HP Touchpad! and at RootzWiki
SDX Version of this thread
Rootzwiki Version of this thread
DISCLAIMER: I'm not a dev, nor do I play one on t.v. Use the information and links at your own risk. Read and understand what you're doing FIRST is the best bet. I take no credit for the original idea, just ran a bit farther out on the branch before it broke.
Afterwards be sure to check out:
[Tips and Tricks] OTG (USB Host Support) - Requires kernel support
My 2 Port 2 Amp OTG Charger & Mod post further down.
This is a difficult modification that requires you to completely disassemble Touchpad (correct tools a plus), cut and dremel out excess material from the back cover (risk of permanent damage) and display frame. You also need to have some soldering equipment plus skill with very small circuit boards/traces (if you want more than a full size power port) and loads of patience (this took several hours over 4-6 separate days).
Still interested? Have a look:
- USB-A Female Connector from a USB Extension cable (and it's spare wire)
(or optional microUSB breakout as FTEN used in his original version)
- Small, thin, SPDT switch (single pole double throw) from a Dollar Store toy, ie "DollarTree"
- VPack PRT-08290 (5v Regulator) and it's PDF Reference file
- micro USB (M) connector from a cable or OTG Adapter (if you can't get the Enable switch landed you'll need this cut up into a plug with the ID pin shorted)
( or maybe AppleCable's Powered OTG Cable )
- Spudger Tool set (or similar for cracking open the TP)
- Variable Speed Dremel with "Rotary File" bit
- Decent Soldering Iron (ie: Weller WES51) with small conical tip, and small electrical solder (LeadFree compatible recommended)
- Hobby knife Set (ie X-Acto with various blades and handles)
- Hot Glue Gun and sticks
Basic Disassembly/Reassembly: iFixit's HP Touchpad Battery Removal Guide
(You should be confident with the above. Be prepared to break a few of the 7 clips; superglue helps).
The Finished Product: