2015-01-30 14:03 GMT+01:00, Kustaa Nyholm <kustaa.nyh...@planmeca.com>: > First of all, I'm talking about existing code and hardware. > > The existing code (without the bootloader) already pretty much > fills the PIC18F4550. > > I can't just willy-nilly move to a bigger device, there is > existing hardware on the field. > I don't think there is a bigger device that is close to PIC18F4550
Are You use DIP version or TQFP/QFN? If TQFP/QGFN there is PIC18F46j50, 64kB of flash, pinout (tqfp/qfn) compatible with 4550 but better, it has PPS (configurable pinout io) and extra low power features. And is cheaper than 4550. > so the bigger device would also mean more than just pop in a > new chip, likely PCB changes and more in hardware and software. Are you trying to say that You are using sdcc with serious (production) projects? Nothing wrong with that, but it sounds brave :-). > Better compiler? > > Yeah, that is an option. However when I toyed with > this idea my SDCC optimised code did not compile without mods > with Microchip compilers. To get a reference point I compared > the compiled size of the Free M-stack and my own HID stack > and the size of the M-stack compiled with Microchip was twice > the size of my own compiled with SDCC. Not a fair comparison but > not an encouraging sign either. > >>Currently I'm using own usbbootloader with xtea encrytption, which >>takes about 10kB in size and I'm pretty happy with it. > > The Diolan bootloader fits in the smaller 1kB boot block... But You have some problems with implementing it, right? >>Writing such >>bootloader is trivial job and it takes a couple of minutes. > > Seriously? Oh c'mon. Free usb hid code (by Alexander Enzmann) "compatible" with sdcc is laying around for a long time, xtea code is even on a Wikipedia page... taking it together, adding write flash code, moving vectors etc. isn't a rocket science. >>I think >>You wasted more time trying to find solution how to fit it than trying >>to write a new, custom bootloader, which meets all Your requirements. > > Seriously? I don't think I've wasted any time yet, except answering > your comment. Oh You take it really seriously, relax. I just try understand why Diolan booloader is worth so much. ml ------------------------------------------------------------------------------ Dive into the World of Parallel Programming. The Go Parallel Website, sponsored by Intel and developed in partnership with Slashdot Media, is your hub for all things parallel software development, from weekly thought leadership blogs to news, videos, case studies, tutorials and more. Take a look and join the conversation now. http://goparallel.sourceforge.net/ _______________________________________________ Sdcc-user mailing list Sdcc-user@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/sdcc-user
