I decided that I wanted to upgrade this router's onboard flash from 8M to 16M (and possibly beyond if possible) because:
1. I like the small form factor
2. it's a great value at ~$17 from aliexpress
3. I hit the built-in storage limit pretty quickly and still wasn't able to add all the modules I wanted. Yes I know about extroot, but the point about this small router is that... it's small, and portable, and pocketable. With extroot it wouldn't be anymore.
So I studied the boot log (https://dl.dropboxusercontent.com/u/107 … utty.log.2) and this version uses an Eon EN25Q64 64Mbit chip (datasheet: http://www.eonssi.com/upfile/p2009111114954.pdf) instead of the W25Q64BV referenced on http://wiki.openwrt.org/toh/nexx/wt3020. No problem, they are compatible. The next chip up from Winbond is a 128Mbit SPI W25Q128FV http://www.nexflash.com/NR/rdonlyres/A5 … Q128FV.pdf which I was able to find at Digi-Key (http://www.digikey.com/product-detail/e … ND/3008697) for $25 for 10 pieces including shipping.
I got the package in the mail today and got to hacking.
1: the original board showing the SPI EEPROM with markings scratched off from factory (heh). The green wires are for the serial console.
2: required for hacking
3: chip unsoldered.
4. original chip in carrier ready to be read. I used a TL866A USB EEPROM reader to make a copy of the original firmware for safekeeping (if you need it you can download it here: https://dl.dropboxusercontent.com/u/107 … are237.7z)
5. replacement chips
6. New larger 16MB chip soldered in; old chip below. Before soldering it I flashed it with the original firmware.
And serial console log showing that the bootloader complains about not knowing what the new chip is, but keeps booting anyway. https://dl.dropboxusercontent.com/u/107 … utty.log.3
Now onto making openwrt use all that extra flash.
(Last edited by stamasd on 24 Dec 2014, 02:31)