[E3-hacking] PBL & running arbitrary code

Matt Evans e3-hacking@earth.li
Fri, 11 Mar 2005 12:59:49 +0000

Howdy David,

On 11 Mar 2005, at 12:25, David Given wrote:

> On Fri, 2005-03-11 at 11:02 +0000, Matt Evans wrote:
> [...]
>> !  Smart media holds /enough/ - Well, enough to hold a kernel that 
>> will
>> then drive USB storage devices ;-)
> Does the E2 have a Smart *Card* socket or a Smart *Media* socket? I
> can't seem to find a definitive spec.
> And does the E2 have a Pocket Docket, or was that only the E1?

Yes yes yes - has a smartcard socket, a smartmedia socket (BTW, where 
the hell can I buy one of these ancient things from these days?) and a 
pocket docket thingy.  (4-pin serial nastiness - probably vcc/gnd and 
txd rxd - wouldn't be surprised if it was usual UART RS232-style data 
format (but at 'TTL' levels probably)).

> I was hoping to avoid all that messy JTAG stuff, but it's obviously the
> way to go.
> The company I work for does embedded operating systems, and
> *rummage around in drawers*
> it took me 15 seconds to lay my hands on an Insight IJC2 parallel port
> JTAG adaptor from some long-defunct piece of hardware, but 
> unfortunately
> my home computer doesn't have a parallel port. Plus, it would appear
> that I'd need to solder pins onto the E2's motherboard to make it work.

Yeah :(  It's pretty easy though, it's brought out to some pads on the 

> Can anyone reccomend any Linux JTAG software? Are there any standard
> interfaces?

:(  Here's where it got annoying for me.  If you have an OCD 'wiggler' 
parallel port cable, then you're in luck (me neither..) because OCD 
Commander is available free (Windows + Linux, nicely), plus IMHO the 
more useful GDB-stub-to-JTAG.  (http://www.macraigor.com/ocd_cmd.htm)  
This will drive ARM's EmbeddedICE via JTAG and looks pretty cool.  I 
couldn't find anything as polished, free, for my JTAG cable under 
linux.  I ended up using libjtag + armtool, which works with a variety 
of parallel port cables.

If you do wire up a cable compatible with Macraigor's cable (the 
schematic of the wiggler is around on the net in various places), that 
looks like a good bit of software.  I'm using Xilinx's JTAG cable - 
it'd be easily modified to use the wiggler pinouts, but I don't want to 
sacrifice it cos I still use it for its original purpose.

> As for the PBL ROM image, I'll drop in to Dixons this evening and get 
> an
> E2 --- then I'll have a genuine license and you can send it to me quite
> legally, muhahaha.

Ahh right ;)