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Re: redboot booting problem
Sivakamesh Thota <thota@cosmic.utah.edu> writes:
> It is a standard board with the above device implementation like UART
> etc. By the way what are these devices(PIC and PIT)???
Programmable Interrupt Controller, Programmable Interval Timer.
> I suppose it may be the problem. But even after disabling this
> CYGPKG_REDBOOT_NETWORKING package, it happens to be the same problem.
> Any debugging techniques to know exactly how far my redboot is goin the
> booting procedure????.
>
You are in luck in that the PC is a relatively easy machine on which
to debug very low level code. This is because you have the memory
mapped display at 0xb8000. There are macros in pcmb_io.h to write to
the display from C, and to write to it from assembler is just three
insructions:
movl 0xb8000,%eax
movw '!'+0x0700,%bx
movw %bx,80(%eax)
Given that the screen does not clear, then the problem is probably
somewhere before the call to hal_platform_init(). Just scatter a few
writes to the display aroung and binary chop until you find where it
fails.
--
Nick Garnett eCos Kernel Architect
http://www.ecoscentric.com/ The eCos and RedBoot experts
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