Description
Details
Parallel port allow the input of up to 9 bits or the output of 12 bits at any one given time. This port may be used for interfacing home made projects since external circuitry is minimal for many simple tasks. The port is composed of 4 control lines, 5 status lines and 8 data lines. Nowadays is obsolete and rarely found on the back of your PC (note, that 25 pin D-SUB male connector may represent RS-232 serial port, which is not compatible with LPT!)
| Pin No (DB25) | Pin No (36 pin) | Signal name | Direction | Register – bit | Inverted | DB25 Pinout |
| 1 | 1 | Strobe | In/Out | Control-0 | Yes |  |
| 2 | 2 | Data 0 | Out | Data-0 | No | |
| 3 | 3 | Data 1 | Out | Data-1 | No | |
| 4 | 4 | Data 2 | Out | Data-2 | No | |
| 5 | 5 | Data 3 | Out | Data-3 | No | |
| 6 | 6 | Data 4 | Out | Data-4 | No | |
| 7 | 7 | Data 5 | Out | Data-5 | No | |
| 8 | 8 | Data 6 | Out | Data-6 | No | |
| 9 | 9 | Data 7 | Out | Data-7 | No | |
| 10 | 10 | Ack | In | Status-6 | No | |
| 11 | 11 | Busy | In | Status-7 | Yes | |
| 12 | 12 | Paper-Out | In | Status-5 | No | |
| 13 | 13 | Select | In | Status-4 | No | |
| 14 | 14 | Linefeed | In/Out | Control-1 | Yes | |
| 15 | 32 | Error | In | Status-3 | No | |
| 16 | 31 | Reset | In/Out | Control-2 | No | |
| 17 | 36 | Select-Printer | In/Out | Control-3 | Yes | |
| 18-25 | 19-30,33,17,16 | Ground | – | – | – |
Today is impossible or difficult to find and buy a new laptop computer or desktop PC with a parallel port
While the parallel port is disappearing from laptop and desktop computers, it is still possible to purchase an inexpensive PCI card that provides you with one LPT port.
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| PCI Slot Parallel Port Card | PCI Express Slot Parallel Port Card | ||||
| This card provides 1 industry standard 25 pin LPT parallel printer port in a single low profile PCI slot. As PCI is fully Plug and Play compatible your BIOS and operating system will automatically configure the card ensuring conflict free installation. | This card provides 1 industry standard 25 pin LPT parallel printer port in a single Low Profile PCI Express Card. As PCI Express is fully Plug and Play compatible your BIOS and operating system will automatically configure the card ensuring conflict free installation. |