Hi,
http://www.machsupport.com/forum/index.php/topic,37410.msg255891.html#msg255891Three companies do a USB to single parallel port device, the UC100 by CNCdrive, the PMDX411 by PMDX and the 57CNCdb25 by PoKeys. All are good and economical and the
companies support their devices well but they only have one port ie 12 outputs and 5 inputs. Suitable for the simplest machines only. Beware places like EBay and Amazon, they sell
Chinese knockoff UC100's. Buy genuine or don't buy!
The PMDX-424 is a two port device with 34 IO's. Has lathe threading but not backlash comp nor THC. Superb quality and backup. No BoB required,
all IO is 'conditioned ' on board and has its own on board power supply. 100kHz output pulse rate max.
The Ethernet SmoothStepper (ESS) is a three port device with 51 IO's. Has backlash comp, THC and lathe threading are being developed but not here yet. Great backup
and quality. BoBs are recommended to buffer the IO's, simple bidirectional C10's at $23.00 each are adequate. Note the USB Smoothstepper from the same company is
Mach3 only. 4MHz output pulse rate max.
The 57CNC has 57 IO's, several of which are capable of analogue input, which makes them flexible. To my knowledge they do lathe threading but not THC. Has a board level
programming feature which adds flexibility if you are prepared to learn to program it. The same company do the 57E and the 57U, Ethernet and USB connected respectively
which operate at a slower pulse rate and with reduced number of axes. They are fully expanded in the 57CNC and is preferred over its cheaper 57E and 57U siblings. Good
quality and support. 125kHz output pulse rate max.
The UC300 has five ports with 85 IO's. Good quality and support. Relative newcomer to Mach4 and has no backlash comp, THC or lathe threading. CNCDrive have not, to my
knowledge, committed to developing any of them. I understand BoBs are recommended to buffer IO's. Good value device with swags of IO. 400kHz output pulse rate max.
The HiCon is a high quality high priced board. Some of the features like THC you have to pay an extra activation fee, likewise for IO expansion and close loop extensions activation fees apply.
Despite the high price many owners report complete satisfaction. Backlash comp, THC and lathe threading are all supported, to be read in conjunction with the note regarding activation fees.
2 MHz output pulse rate max.
Galill is professional quality gear, expect to spend in excess of $2000. Extensive board level programming ability, IO expansion and pulse rates up to 22MHz, you could Gcode a radio station!!!
If you can afford one of these...would you get me one too!
CSLabs have a Mach4 plugin but its buggy. Worse CSLabs have slipped in their once enviable reputation for support and are slow to fix faults. Given the price being sort hard to recommend.
XHC has some Mach4 ready devices, but I've heard of one person only who has had any success with them. AVOID LIKE THE PLAGUE!
Craig