It's possible to display custom text on the pad's LCD during signing. This function allows to define custom text for one line of the LCD. For built-in 8x8 font there are 30 lines available, each of them is 40 characters width. Text will be drawn on the call of startRead function.
By Devices with Colour Displays an additional LCDImageExR(5, 0, 0, 0) call is required. The LCDImageExR call also contain another background image, in that case the deviceapi will merge the text and the image before the upload.
Line number, starting from 1.