FD70 supports FS11, FD12 and PWD message framing (a header and a footer). The message content (body) is sent between the header and the footer.
Enable frames in messages and toggle on header and footer in data messages with the command:
set com1.message1.framing ON
Enable FS11 framing with the command:
set com1.message1.emulation FS11
Enable FD12 framing (default framing method) with the command:
set com1.message1.emulation FD12
Enable PWD framing with the command:
set com1.message1.emulation PWD