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Building the XH1541 Parallel Cable

Parts needed:XH1541 cable parts

Visit the ports, parts & pinouts page for a descriptions of all the above parts.

Tools needed:

This is called a "hybrid parallel-only" cable, and it requires the use of a companion serial cable. It is compatible with older parallel ports (standard and PS/2) and thus doesn't work on contemporary hardware. It is a semi-parallel cable (full parallel one way, half-parallel the other) thus allows for limited high speed transfers. You must have the C= parallel option installed in your disk drive in order to use this cable. Due to its pinout and more complex construction requiring eight diodes, it can only be combined with the X1541 to make a XXH1541, or on a system with two parallel ports which it can then be combined with any of the serial cables. It is not recommended to build this cable or the XXH variant due to its limited usefulness, software support and its requirement for older parallel ports. Instead, look at the XM1541, XMP1541, XA1541 or XAP1541 for better options. This cable only works with Star Commander.

If you're not sure this is the right cable for you, see my cable picking guide to check.

Since I have never built this cable, no pictures are possible and thus the following building instructions have not been tested.

XH cable copyright Bigfoot, 1997


Step 1: Prep the DB15 connector and attach the diodes and wires

This process splits the installation of the diodes into 2 groups of 4, one group in the DB15 and one in the DB25. This alleviates some space issues in the DB25 if all 8 diodes were installed there.

Note that this cable contains no ground line and requires the use of the companion X1541 cable to provide the ground. A ground line in this cable could cause a ground loop condition, something which must be avoided. Also, the parallel port add-on to the C= disk drive doesn't contain a ground line for this very reason.


Step 2: Prep the other end of the 8 conductor wire and attach to the DB25


Step 3: Check the cable

Cable pinout chart

DB15 (male)
DB25 (male)
1 (PB0)
-->|-- 2 (DATA0)
2 (PB1)

-->|-- 3 (DATA1)

3 (PB2)
-->|-- 4 (DATA2)
4 (PB3)
-->|-- 5 (DATA3)
5 (PB4)
-->|-- 6 (DATA4)
6 (PB5)
-->|-- 7 (DATA5)
7 (PB6)
-->|-- 8 (DATA6)
8 (PB7)
-->|-- 9 (DATA7)
1 (PB0)
13 (SELECT)
2 (PB1)
12 (PAPER END)
3 (PB2)
10 (ACK)
4 (PB3)
11 (BUSY)
18 to 25 shorted

Step 4: Finish the cable. Mount the DB ends in their hoods


XH1541 schematics

Schematics drawn using ExpressPCB, a free and excellent solution which also supports PC board layout editing.


Email the author: Peter Schepers | Last updated: Mar 17, 2009