writing to the display of a pinpad reader

Hello folks,

I have a ct710 reader from Gemalto.
The pcsc name for it is:
Gemalto Ezio Shield (S14C0138571943) 00 00

I want to write a string to the display using pcscd on linux with the 
libccid driver.
Can anyone help me to find out how to do it?

First I tried to use SCardControl with FEATURE_WRITE_DISPLAY but found 
out that this is not implemented by libccid.

My recent idea is to use SCardControl with FEATURE_CCID_ESC_COMMAND. But 
I don't have any documentation of escape commands for the reader. Does 
anyone know where I could find such documentation?
I have already tried gemalto.com but they neither have any documentation 
nor support for their readers.

Alternatively I could get another pinpad reader.
Does anyone know how writing to the display of any reader is done with 
the pcsc API ?

Any help would really be appreciated.

Cheers,
Lars