Simtrace prototype progress

Hi all, Kevin and I have been making great progress today, spending about 12 hours with debugging, re-working and re-designign simtrace. The previous malfanction seemed to be caused by attachign the Vcc from the phone to the AD7 input of the SAM7. Apparently the Vcc of the phone was >= 50mV higher than the Vcc of the SAM7, and this caused the phone (/smartcard reader) to give up as it could not raise the power line to the level it wanted to raise it, even before switching on clock to the card. Aside from the one prototype, we have also received 5 units made by some friends of K2 in china, who unfortunately used a previous gerber that had even more bugs. Nonetheless, three out of those 5 units have been re-worked, and are now functional, too. We will do a very quick 2nd prototype spin with the following changes * fix all the bugs as per the trac tickets * use the new bus switch with lower resistance * use a LDO with two outputs (and two enable inputs) so we can use a GPIO to supply the SIM card with voltage ourselves * add a power distribution switch with < 1Ohm Rds-on so we can alternatively switch through the Vcc from the phone to the SIM * add a resistive divider between VCC_phone and the ADC input * use angled jumpers so the overall unit remains flat The gerber will be sent off tomorrow for a '3 working days' quick PCB, the corresponding digikey order, too. Kevin has offered to solder the next prototype. If everything works well, we will immediately go into production of something like 100 units to make sure they're ready before the CCC Camp (where some people might be interested in obtaining one). Regards, Harald -- - Harald Welte &lt;laforge(a)gnumonks.org&gt; http://laforge.gnumonks.org/ ============================================================================ "Privacy in residential applications is a desirable marketing option." (ETSI EN 300 175-7 Ch. A6)