USB keypad with FTDI RS232 chip

Hi everybody, the recent talk about FTDI USB/RS232 chips reminded me of this... Sometime ago, I bought a numeric USB keypad with a two-line dot matrix LCD on top on a flea market. This piece of hardware is designated DATACOMP Electronics co., Ltd. Model No.: DLK18U_100AL and has a marking referring to "alphyra" (which seems to have been a now-defunct/absorbed e-payment outfit) above the display. It has 18 keys (4 blank, ESC (red key body), numeric keypad "0"-"9",".", backspace (left arrow), and Enter (green key body)) and shows, IIRC, "Version 1.0" on the display when powered. The .tw-based manufacturer is alive and even has a driver download for it, which seems to be nothing more than an FTDI serial port driver providing a new COM port on my computer. The FTDI chip inside the keypad is attached to an EN78P447xxx device, which I found out to be an OTP microcontroller. What I unfortunately wasn't able to find yet was any description how to talk to/what to expect from this port. Listening on the COM port at various speeds with the usual 8n1 parameters and pressing keys on the keypad yielded nothing, so there's probably some sort of initialization necessary. A long shot again I know, but if somebody has experience or documentation regarding this keypad that may be shared, then please contact me. Yours truly, Arno Kletzander