The Problem: System comes up with a double-beep and a message XX 301, Not-Okay and "RTFM"-symbol|
The Cause: One or more keys stuck on the keyboard
The Solution: Take your fingers, books or animals off the keyboard and reboot. If error comes again: look into the table, which key is stucked
The XX before the 301-error is the scan-code of the corresponding key, which is recognized to have stucked. If E0 or E1 is displayed, one of the 'special keys' is sending the first half of their 2-byte code to the system.
Just try it out on a running system: reboot and hold one key until the system restarts.
101-keys Keyboard (US/UK-style)
General Keyboard Maintenance|
Most of the original IBM-keyboards have separate keycaps, which can be removed very easy. Under this cap sits the key-'corpus' and underneath a small spring. This spring is fixed with a contact-plate inside the keyboard.
In case you accidently removed the key-button entirely from the keyboard:
You will have to remove the keytop in case some dirt (mainly coffee or Coca-Cola) sits between keybutton and the collar. Keys then tend to stick, the feeling while pressing the key is somewhat soft and sticky and the 'click' after releasing the key is somewhat delayed. Cleaning inside of the button (...not the cap !) and the key-collar with alcohol will mostly solve these problems.|
It is a good idea to maintain the keyboard frequently.
Remove all keycaps except the space-bar and probably the two larger keys on the right side ([+] and [ENTER] from the numeric keypad). These keys have additional metal guides at the underside and are hard to re-assemble.
Use a longhaired, harder brush to clean the areas around the keys from dirt. In most cases this is just dust, but sometimes there are hair-needles, nails, screws, clamps and other stuff. Turn the keyboard upside down and shake it ... !
Cleaning the dirty, sticky keycaps is easy if you have a washing-machine or a dishwasher. I prefer dish-washers.
I use the same procedure on the entire keyboard housing by the way. It is quite easy to disassemble. 3 hex-screws from the underside, remove keyboard assembly and internal circuit board and put the two housing halves in the dish-washer too.
Now: this is much harder if you have only a washing-machine. It is Not recommended to treat the keyboard housings this way - they will break in pieces. The keycaps can be washed as well. But not too hot. I had good results in pre-washing with 30° C and put them inside of one old nylon stocking. Basically the same procedure as with the dish-washer ...
Most problems come from the keyboard cable. If the keyboard is totally defective, causes the computer to beep perpetual, does not respond at all or has all LEDs continously on or rapidly flashing ... there's not much one can do than disposing the thing.
The cable however can be tested with a multimeter in Ohms-range.
Here's the pin-out:
Check all wires for continuity, all connectors for broken or bended pins. Dispose broken keyboard cables.|
If all appears to be in good order, suspect keyboard or systemboard to be defective.
Errorcode 305 at power-up means "+5 VDC on keyboard missing".
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© 1997 by Peter H. Wendt / pw-software production