Hi,<br /><br />&gt; I would like to run the c123(s) without the LI battery with direct<br />&gt; 5V power supply only. Without battery the c123 display just blinks<br />&gt; and no PROMPT1 can be received.<br /><br />That won&#39;t work via the power plug ... (at least with osmocom, with the default FW it may works if you have a big cap instead of the battery).<br /><br />You can inject 3.7v directly at the battery pins with a big cap close to the phone and that should work fine.<br /><br />Check the C118 schematics to understand why.<br /><br />Cheers,<br /><br />    Sylvain