How to recover fail BIOS update on A200 ??

Ooh, a freeze during a BIOS update is usually a death knell. Most likely the only way you're going to be able to use the computer again is if you send it in to Toshiba and they either re-flash the BIOS on the EEPROM chip or replace your motherboard. Unfortunately, the CMOS battery has nothing to do with your problem and there's really nothing you can do by yourself.

What Djembe says is correct and a few years back it was about $100.
Just because there is a new BIOS update does not mean it is applicable to your machine.
BIOS upgrades are for specific problems and if your machine is not encountering those problems, a dead machine is what you get. Please remember, newer is not always better so dont try to fix something that isnt broke

Yeah you have probably hosed the laptop.... However it is worth trying some stuff....

Download the latest BIOS from here .....

Use the winXP and it downloads as an executable which makes it a PIA, so do not execute it on the PC you download it from, but extract it using an ZIP or RAR program, which should leave you two files - the .exe file and a ROM file...

Now you have that, forget that for one moment and start the laptop up whilst holding the FN and B key and see if this pushes the laptop into recovery mode.. If this works , good... If it doesn't, things get a bit more complicated...

I always have USB floppy drive and discs for this purpose, old but useful... Copy the .exe file and the ROM file to a floppy and plug the floppy into a USB port on the laptop... Power up the laptop and hold the FN and B key down until you see the light come on the floppy, then release... Again this may/may not work...

If you don't have a USB floppy to hand you need to make a bootable USB stick (use an old one, cos making it bootable erases all the data on it, again why I have some old 1Gb ones to hand).. Download the HP USB tool here .. Extract the file and follow the onscreen instructions to make the drive bootable... Once done, then copy the .exe file and ROM file over to the USB stick and follow the same procedure....

Now I am pretty sure the recovery mode on Toshiba is FN and B, but it may be different, so let me know how it goes.. And again, it doesn't always work, but its always worth a try...

If you can solder, you can replace the BIOS chip yourself:

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