Upgrading the flash memory

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While netbooting the 5861 to use the latest v6 firmware is not much of an issue, having a 2MB router is always better...especially if you can convert a standard ex-BT 1MB one
Just one small point YOU CAN DESTROY THE ROUTER COMPLETELY is you are not careful...you have been warned!!

Before you start check the photos carefully (they are large on purpose!!) so you are aware of what you will need to do. Also you will have to obtain an ultrafast AND gate such as the NC7SZ08M5 (Farnell 345-7862), a small precision soldering iron and a pair of tweezers.

The area we will be working on is near the flash memory shown below on an unmodified board.

Remove the existing link to pin A20 (the blue wire in the example).

Fit the AND gate in position on the board, it can be positioned as in the photo below. This not only makes connection the supply/ground easier, but also keeps the lead as short as possible, which is an advantage on high speed circuits.

Solder the ground directly to the decoupling capacitor, and the supply to the opposite side. Connect one input of the AND gate to the chip select signal to the right of the flash chip. The other is connected to both pin A20 of the flash chip and on the reverse of the board (see other photo).

By far the hardest part is connecting the AND gate output to the CE pin (pin 9) of the flash chip. This pin will need to be lifted from the board first by means of the small tweezers (or screwdriver), remember DO NOT overheat the chip!! Also when lifting the pin be aware that it can easily break off!!

Once complete power up the router, while the boot loader will see the extra flash memory the file system will still report only 1MB.

# msfs Filesystem 0, size=825k :

Backup the ASIC.AIC and any key files from the router. This is important!!
Next clear the file system with the format disk command. When this has completed install the new kernel and replace the ASIC.AIC file. Reboot the router and it should report that it now has 2MB of flash.

superuser@console-> msfs Filesystem 0, size=1841k :

You can now look forward using v6 firmware without having to netboot!