First of all, the Cumulus project now has a home page :).
I’ve made a couple of important updates to the Cumulus firmware. First, I made sure that support for both Epson and Phillips LCD controllers is in place and working well (Nokia 6610 LCDs come mainly in these two flavors, as is well known now). There are a few relevant differences between the controllers, mostly in initialization of the controller and handling of screen orientation.
I also implemented bootloader support (i.e. SD card firmware update). It proved to be a little trickier than I first thought, mostly due to compiler issues and a misleading example from Microchip. The main issue was that the compiler does not actually load the table pointer for the erase operation unless you actually issue a dummy read operation first. Now it all seems to be working fine. Right now, the bootloader is larger than it needs to be (there is an embedded font I used for printing debugging messages on the LCD) and verification is missing but these are easy to fix and finalize (before a binary firmware release is made).
I’ve also populated one of the CumuluBus boards that I received and I am glad to say that it works fine.