Can my titanium application communicate with external hardwares.

Hi, am currently using Titanium Studio version 3.2.1 and Mac system with mountain lion OS. Am developing an application for external hardware device on which my iphone will be mounted and connected to through serial connection, setup can be used to read the magnetic card details, once you swipe the card in external hardware. All went smoothly when i have build the application for native ios platform. But when i created the modules and integrated with titanium application, am not able to communicate with hardware device. What might be the problem? None of my commands are working. Is there any specific protocol i need to fallow or what am following in native application is enough to work?.

uint8_t ui8Buff[0xff];
    ui8Buff[0] = 0x1d;
    ui8Buff[1] = 0x6c;
    [[session_ipos outputStream]write:ui8Buff maxLength:2];