Sio-Mode: Usb Pc-Adaptor Cable With Hardware-Handshake - Sharp PC-G850VS User Manual/ Interface

SHARP PC-G850V(S) User Manual - Appendix A: 11-Pin Interface
SIO-Mode: USB PC-Adaptor Cable with Hardware-Handshake
An elegant, hence powerful DIY-alternative for the connection of the PC-G850V(S) with a
modern PC is based on a pre-built USB-UART adaptor cable with open endings.
Specification:
FTDI USB-UART/TTL adaptor cable based on FT232R-chip, 5V, 6 pins
(GND,5V,RXD,TXD,RTS,CTS)
For physical connection with the 11-pin interface of the PC-G850V a common multi-pin-
connector with 2.54mm spacing can be used. You need to solder the UART-lines of
adaptor to the multi-pin-connector by using a null-modem wiring then:
FTDI-UART
Signal (Color)
GND (black)
RXD (yellow)
TXD (orange)
CTS (brown)
RTS (green)
VCC (red)
Additionally there should be a 10kOhm resistor between pin-4 and pin-3 of the multi-pin-
connector. It serves as a pulldown for the RTS-signal, to get a defined LOW level.
Without it, you might experience I/O-errors when transferring data from a PC to the PC-
G850V(S), because the PC may not receive wait requests from the pocket computer.
Finally you have to download the tool FT_PROG from the website of the manufacturer:
www.ftdichip.com. With this tool you must logically invert the signals RXD, TXD, RTS and
CTS of the FTDI-chip, because the SIO-mode (RS-232 interface) of the PC-G850V(S)
operates on inverted UART-logic (see above). This is a one-off process and the settings
are persisted within the integrated EEPROM of the FTDI-chip.
PC-G850V(S)
Signal (Pin)
GND (3)
TXD (7)
RXD (6)
RTS (4)
CTS (9)
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