Simple.
1) Download Firmware from Pentax.
http://www.pentax.jp/english/support/digital/k-5_s.html
2) Unzip so that a .bin file is created with a readme. Read the readme if you want to, as it has instructions on it.
3) Take the .bin file and put it on a blank formated SD card.
4) Put the card in the K5.
5) Turn the K5 ON while holding the menu button
6) Let the card/camera do it's thing.
7) when the little status light blinks on the back of the camera, and the LCD says complete, just turn off the camera.
8) You can then turn on the camera, and format the card to remove the firmware and have a freshly formatted card.
9) done.
Here is the text from the readme.txt
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Updating Procedure
1. Provide a formated SD/SDHC memory card for the update software (with at
least 32MB of available memory space).
The downloaded file is self-extracting.
The following files are extracted.
readme.txt : this document
fwdc209b.bin : Firmware
Copy the above Firmware file [fwdc209b.bin] to the root directory in
the SD/SDHC card.
If your computer does not have a card slot, you can copy the firmware
update file by inserting the SD/SDHC card into your camera and then
connecting the camera directly to your computer.
2. Insert the D-LI90 battery into the camera and confirm the battery is full
by battery level indicator then turn the camera off.
3. Insert the update SD/SDHC card (prepared in step 1) into the camera
and close card cover.
4. Turn the camera power on while pressing the MENU button.
5. "NOW LOADING" appears in the LCD monitor, and will change to the
"PROGRAM UPDATE". At the bottom of the LCD monitor,
CURRENT VERSION 1.00/1.02/1.03/1.10/1.11/1.12/1.13.
UPDATE VERSION 1.14
will be displayed.
6. Press the four-way controller to select "YES" and press the "OK" button.
7. "UPDATING" appears on the LCD monitor and updating starts.
Please do not under any circumstances switch off the power before the
update is completed.
It will take approximately 90 seconds to complete update.
8. When update is completed, the "COMPLETE" will be displayed at the left
bottom of the LCD monitor, then turn the camera off.
9. Remove the update SD/SDHC card from the camera.
10. To check the Firmware version in your camera, turn the camera on while
pressing the MENU button.
Check that the version displayed in the LCD monitor is "Ver.1.14"
The camera automatically starts up after about 5 seconds.
(Caution)
When updating is finished, the update SD/SDHC card still contains the
Firmware file.
If you want to use this card to take pictures, delete the Firmware file
first.
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