[E3-hacking] Re: E2 PBL bios dump.

Ralph Corderoy e3-hacking@earth.li
Mon, 21 Feb 2005 23:07:19 +0000

Hi en4rab,

> I also had an idea for recovery of the bios of the E3, has anyone yet
> worked out if the Jtag port of the CPU in the E3 is taken to a usable
> header on the e3's board.

Or to some test pads immediately underneath the OMAP5910 SoC?  If anyone
does have their E3 in bits, a photograph of the top and bottom of the
main PCB good enough to read IC lettering would be helpful.  Using a
flat-bed scanner can be a good way to achieve this, but make sure not to
scratch the glass.

> According to the datasheet for the e3's cpu the jtag pins are at
> locations U15, U16, U17, T14 and R13 (the jtag signals are called
> (nTrst, TDO, TDI, TMS and TCK off hand i cant rember which pin is
> which)

    Signal  GZG   GDY
           Ball  Ball
    TCK     W18   T14
    TDI     Y19   U17
    TDO    AA19   U16
    TMS     V17   R13
    /TRST   Y18   U15

> I think the jtag interface from tailor-madecircuits,
> http://www.tailor-madecircuits.com/jtag_interface.htm , should work
> for dumping the bios but it doesnt have the nTrst circuitry, but I
> think it will work, but be warned TMC have had a run on these so there
> is a bit of a delay on them.

Thanks for the URL, I wasn't aware of them.