Crossover or "Null Modem" vs. Straight Through Serial Cable - Decisive Tactics, Inc.
Delock Products 86604 Delock Serial Cable RS-232 D-Sub9 female to female null modem with narrow plug housing 10 m
Null modem - Wikipedia
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FTDI Chipset Cross Wired USB Seriële DB9 FT232R USB RS232 Null Modem Kabel Pc Control TV Kabel (Standaard DB9 COM poort pinout (pc (host) met usb naar RS232 terminal apparaat (slave)) :
Null modem - Wikipedia
Should I Use Null Modem or Straight Through Serial Cables? - NI