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Rockbox mail archiveSubject: Rockbox won't start from flash, any ideas?Rockbox won't start from flash, any ideas?
From: <idc-dragon_at_gmx.de>
Date: Wed, 25 Jun 2003 14:21:58 +0200 (MEST) Hello, frequent readers of this may know that I'm working on getting to Rockbox start from flash memory, kicking out the original firmware. The reward will be a much faster "On"-to-music time. Irony has it that I have one of the few boxes with the wrong flash chip, not in-system programmable. But a new one is on order, I'm desperately waiting for it. Meanwhile I have built my toolchain for UART boot (requires the serial mod). With a little extra hardware mod (pulling the LCD lines low instead of high) I can exploit a mode where the boot ROM expects code from the UART. A PC application now transfers a little monitor program to the internal RAM. When that's done the two can talk, the current command set allows memory read/write and jumping to an address. This is sufficient to program the flash (even if completely garbled, because UART boot comes before flash boot) and other tricks. Currently I'm "practicing" to start Rockbox. To do that, I use the monitor to configure the DRAM controller in the same way the flash boot does. When I have the DRAM available, I load the rockbox binary into place and jump to it. Expectedly, this didn't really work. The big difference is that I "cold start" rockbox, with no firmware running ahead of it. In the normal case, Rockbox is loaded into an environment where "the bed is already made", the firmware has already initialized much of the hardware. All it currently does is switching on the backlight for a few seconds, then shutting it off again. No splashscreen, no harddisk activity. A bit disappointing. Does this ring a bell to anybody, what initialization might be missing? My next plan is to use my toolchain to not load rockbox, but the gdb stub. That can in turn load a debug version of rockbox and allows to step around there. However, my past experience with gdb (under Windows) is no good. The target connection was very unreliable, the debug application was often frozen and had to be killed. Is anybody debugging the box under Windows? Maybe I can persuade a Linux guy with gdb to do the UART boot mod? So long, Joerg -- +++ GMX - Mail, Messaging & more http://www.gmx.net +++ Bitte lächeln! Fotogalerie online mit GMX ohne eigene Homepage!Received on 2003-06-25 Page template was last modified "Tue Sep 7 00:00:02 2021" The Rockbox Crew -- Privacy Policy |