Octagon 5266, Справочное руководство

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Creating a printer cable
The LPT port requires a custom cable to route the signals from J7 to a printer. Do
not use a standard 26-pin to DB-25 cable, as that would route +5V to pin 2, and
would route the rest of the signals to incorrect pins.
To build an LPT cable, use a DB-25 connector, a 26-lead ribbon cable, and a 26-pin
Amp 746288-6 connector.
Pin 1 on the ribbon cable is red. This goes to pin 1 on the DB-25 and the 26-pin
connector. Cut wire 2 at the 26-pin connector. This signal is +5V, and must not be
routed to the DB-25. Swap wires 25 and 26. The ribbon cable can then be straight
connected to the 26-pin connector and the DB-25. Figure 9–1 shows a custom
printer cable for J7. Table 9–1 shows how the J7 signals are routed to the DB-25
once wire 2 is clipped, and wires 25 and 26 are swapped.
Note You must use J7 pin 26 for a ground. That is the only true ground on the connector.
All other signals are routed through an FPGA.
Figure 9–1 Custom printer cable
Cut wire 2
Swap wires 25 and 26
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