Sio-Mode: Rs-232 Standard And Conventions - Sharp PC-G850VS User Manual/ Interface

SHARP PC-G850V(S) User Manual - Appendix A: 11-Pin Interface
SIO-Mode: RS-232 Standard and Conventions
The PC-G850V(S) in SIO-mode exposes the signals of the RS-232 standard, but with
different voltage levels (see below). This section provides the necessary basics of the
standard and covers some specifics of the PC-G850V(S).
Within the RS-232 standard the terms DTE (Data Terminal Equipment) and DCE (Data
Communication Equipment) are introduced. The DTE is the PC-G850 for example and
the DCE is a modem or another peripheral device, like a serial printer.
When two computers shall communicate directly (i.e. without a modem), you need a so
called null-modem (cable/adaptor), which connects the outputs of one DTE with the
inputs of the other and vice versa (crossed signals).
Typically 25-pin (Sub-D 25 / DB-25) or 9-pin (Sub-D 9 / DB-9) plugs and jacks are used
to connect RS-232 capable devices.
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