One thing to note is that when you do this if you input and output using ASCII vs ISO there's a difference and you'll need to set 139.0 to 1 for ASCII. Also, you set 6005.0=1, I didn't know that sequence number calls worked on external subprogram calls? I assume it would also allow me to have multiple M99's in the external subprogram. If so that would make my life a bit easier with a new program I'm writing. Edit: FYI it works on a 35iB too but I've had issues with new memory cards and pcmcia adapters. Even reformatting and reducing the partition size. I have mine working with a 32MB card FAT formatting with 2048 byte allocation. I'd recommend getting a PCMCIA adapter that is PCMCIA version 2 at most. I believe my problems were with the adapter allowing version 3 and the new cf card allowing high speed data transfer since repartitioning the 2GB cf card to 32MB with 2048 byte allocation did not work.