The XA1541 active cable is a serial cable that connects Commodore machines or drives to the PC parallel port.
It has been designed to work in all modes of all parallel ports on all PC motherboards. It\\\'s compatible with all parallel ports and with all Commodore machines and drives and clones that have the usual serial bus port.
Hardware requirements
You need the following hardware to make use of this cable:
•	A PC with a parallel port
•	A Commodore 64, 128 or VIC20 machine or a Commodore 1541, 1570, 1571 or 1581 drive, or any other Commodore machine or drive or clone that has the usual serial bus port

The XA1541 active cable
Important notes
•	You definitely need BSV52 transistors and 4.7 kOhm resistors for this cable, different parts may make the cable inoperable.
•	On circuit diagrams, plugs are displayed as viewed from the back side, the solder side. Chips are displayed as viewed from above; also, see the small semicircular cut for finding the correct orientation. When in doubt, see the corresponding description on the legend page.
Construction
You need the following parts to build this cable:
•	One solderable 6-pin male DIN plug (Commodore serial plug)
•	One solderable 25-pin male plug (PC parallel plug)
•	Four BSV52 transistors
•	Four 4.7 kOhm resistors
•	A shielded 4-wire or unshielded 5-wire cable of, preferably, at most 2 meters
Step 1. Solder one end of the cable onto the DIN plug.
Step 2. Solder those wires, that don\\\'t go through an amplifier, on the other end of the cable onto the parallel plug. These include the following connections:
DIN plug 	Parallel plug 
2, GND 	18-25, GND 
3, ATN 	13, Select 
4, CLK 	12, PaperEnd
5, DATA 	10, Ack 
6, RESET 	11, Busy 


Step 3. Build the amplifier bridges, consisting of one transistor and one resistor each, between the appropriate pins of the parallel plug. These include the following connections:
Parallel plug 	Parallel plug 
13, Select 	1, Strobe 
12, PaperEnd	14, AutoFeed
11, Busy 	17, SelectIn
10, Ack 	16, Init 


The collector of each transistor should be pointing towards the pin in the left column of the table. The base of each transistor should be connected to one side of the resistor; the other side of each resistor should be connected to the pin in the right column of the table. The emitters of the transistors should be connected together to the common ground, the GND line.
Circuit diagram