I am a device driver programmer working with TM-T88V POS printer.
The main problem I am facing is to get the handle (control) for writing to the port. As I am successful in getting the handle during create file using VC++. Up to my research EPSON creates some virtual port during read/write operation. So, accessing the same port is quite tricky process which you can say is monopoly of EPSON.
Aside, we are into touch with EPSON team to get the favorable response. But, until this date they are only stressing on already provided APIs to use. And these can be used while in application programming only. We are successful in getting test prints using the Advanced Printer Driver (APD) provided by EPSON. My printer is attached with USB port. The same code is working fine with other make of POS printers.
If I use the system where EPSON driver is never installed. I mean just inserting the USB printer port, it should plug and play (PnP). But status pop up balloon displays that this printer is not having the driver and it may not work properly. Henceforth, no symbolic name found in the registry entry.
In case of other make of printers I tested and it detected the printer the very first time.