Keywords: USB, LPT, parallel, parallel port, printer port, converter, adaptor
To USB2LPT — Overview
SJ1 | Assignment of pin 25 of D-sub female connector | |
---|---|---|
right connected | Pin 25 to ground (default) | |
not connected | Pin 25 unconnected | |
left connected | Pin 25 to 5 Volt (or 3,3V if SJ4 is right-connected) Instead feeding 5 V directly, a self-rearming fuse like Reichelt PFRA040 is recommended | |
SJ2 | Deactivation of boot EEPROM | |
connected | EEPROM active (connected to microcontroller) | |
not connected | EEPROM disabled (disconnected from microcontroller), the microcontroller defaults to a Cypress USB device | |
SJ3 | Write-protection of boot EEPROM | |
right connected | EEPROM writeable | |
left connected | EEPROM write protected | |
SJ4 | Pullup voltage | |
left connected | 5 V Pullup (compatible to true parallel ports) | |
right connected | 3,3 V Pullup (recommended for non-5V-capable inputs, like Xilinx Spartan FPGAs) |