RAM : 18kb and 50 ko available with RP-33 extension memory. Doesn't accept RP-8 ? To be verified.  Image produced by PockEmul emulator showing specific menu with file option  This option is not available on Z1 and fx-890p models. It is the only difference.
 The back othe machine with the location for the RP-33 extension memory.
 It's possible to upgrade it to 256kb by replacing internal ram by two 128ko ram.