Null Modem Cables: Wiring, Adapters and Pinouts
A null modem cable crosses TX and RX to join two computers directly. Covers DB9 and DB25 pinouts, adapters versus cables, gender changers and loopback testing.
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Serial, SCSI and legacy cabling
RS-232 pinouts, null modem cables, USB-to-serial adapters, RS-422 and RS-485, SCSI and SAS, parallel printer and telco cables.
Parallel Printer Cables: IEEE 1284, DB25 and Centronics
IEEE 1284 parallel printer cables explained: DB25 and Centronics 36 connectors, cable length limits, modes, and when a USB-to-parallel adapter works.
RS-232 Pinouts: DB9 and DB25 Explained
Complete RS-232 pinout reference for DB9 and DB25 connectors: DTE and DCE pin assignments, voltage levels, cable limits, and the TTL mistake that damages boards.
SCSI Cables, Connectors and Terminators
SCSI cable types explained: 50-pin, HD68 and SCA-80 connectors, narrow vs wide buses, SE, LVD and HVD signalling, termination rules and length limits.
SAS vs SATA Cables and Connectors
SAS and SATA cables compared: speeds, SFF-8087 and SFF-8643 connectors, breakout cables, drive and controller compatibility, and cable length limits.
RS-422 vs RS-485: Differential Serial Compared
RS-422 is one driver to many receivers; RS-485 is a true multipoint bus. Compare distance, speed, termination and wiring, and see what damages hardware.
25-Pair Cable, RJ21, Hydra Cables, T1 and V.35
25-pair cable colour code, RJ21 connectors, hydra cables, T1 pinouts and V.35 links: what each carries, how far, and where a wrong connection damages hardware.
USB to Serial Adapters: Drivers, Levels and Pitfalls
How USB to serial adapters work, why drivers and counterfeit chips matter, RS-232 versus TTL levels, and how to get old DB9 equipment talking again.