The PC parallel port

Port modes

The most important feature of the parallel port of your PC is its mode. Possible modes are SPP, PS/2, EPP and ECP.

On 286, 386 and older 486 machines, the parallel port is on a separate card (e.g. I/O card, parallel port card, Hercules video card with a built-in parallel port) and it is SPP or PS/2. If it isn't then you might find jumpers on the card to set the mode. Refer to the documentation of your card for more details.

On newer 486 and all Pentium (and above) machines, the parallel port is integrated onto the motherboard and you can set its mode in the BIOS setup. The usual aliases for the SPP mode are "Compatible", "Normal" or "Standard". "BPP" and "Extended" usually stands for the PS/2 mode and "Enhanced" for either the EPP or the ECP mode.

However, on most Pentium and above motherboards, setting the parallel port to SPP mode won't give you a true SPP port because of the slight changes in the electronical layout of the parallel port.

Don't rely on what port mode your BIOS setup shows. Rather check the real mode of your parallel port with LPTDetect or The Star Commander.

SPP mode means bidirectional control lines and unidirectional data lines. The X1541 cable makes use of the bidirectional control lines. PS/2 differs from SPP in that its data lines are also bidirectional. EPP and ECP offers several enhanced features, that PC software can make use of, but the control lines are not bidirectional anymore in these modes.

If you are interested in the electronical details of PC parallel ports and the X1541-series cables, please, read the Technical background information section in The Star Commander documentation.


Here's a compatibility chart between cables and parallel ports of different modes.

X1541-series cables

X1541 cable [1] YES YES no
XE1541 extended cable [2] YES YES YES
XM1541 multitask cable [2] YES YES YES
XA1541 active cable YES YES YES
XH1541 hybrid cable YES YES YES
XP1541 parallel cable no YES YES

  1. You can check if your parallel port is compatible with the X1541 cable with X1541Test.

  2. We found that the this cable doesn't work on certain motherboards and laptops. See the info page more details. On incompatible machines, it is recommended that you use the XA1541 active cable instead. Unfortunately, there's no software that would be able to tell whether your parallel port is compatible with this cable or not.

Other Commodore-PC cables

1541EMU cable YES YES YES
PC64 cable YES YES YES
Power-Loader cable no YES YES
X1531 cable YES YES YES

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