[RC232] I would like to know how to use the pins N°27 and 28 on the RC2500HP Pin 27 and 28 must be left open. Last Update: August 8, 2017 December 20, 2016 2247 RC232 Q&A Related Knowledge Base Posts -[RC232] Regarding the RC1740HP-RC232, when referring to the region “worldwide”, what does that mean? What certification is available for “worldwide”?[RC232] Can I load my own FW on the module?[RC232] Do your radios have any kind of Listen Before Talk feature ?