The MB2 breakout board from CNCRoom is a good alternative also.

http://www.cncroom.com/break-out-board/smooth-stepper
 
MachBob2 (MB2) is designed for industrial application and specifically to work with the Ethernet
Smooth Stepper (ESS) which is an excellent motion control board designed to be used with Mach3
and Mach4

Here are some of the good features.
 - New! Utilizes all three ports from the ESS.
 - New! Accept frequency up to 4 MHz.
 - New! Differential line driver for motion signals enables longer wiring with more resistance to
   interference when compared to TTL open end.
 - New! A single 24Vdc Power Supply is needed. There is a 5Vdc isolated and non‐isolated dc2dc
   converter on board, thus saving installation space and wiring.
 - New! OSSD (Output Signal Switching Device) outputs and safety circuit are implemented when a
   peripheral device such as a servo motor drive or a spindle VFD trigger an alarm condition, which
   causes the Safety Circuit to disengage the OSSD output. This method is used in large CNC machines
   to cut power from the drives.
 - New! LED status for all inputs and outputs including motion control signals. This makes it much
   easier to diagnose and trouble shoot.
 - New! Polarity and over voltage protection (in conjunction with a fuse) for the 24Vdc power supply.
 - An “AnaSpeed” circuit has been implemented. This circuit is totally isolated from the MB2 and forms
   a part of the VFD inverter, acting as a digital VR. High voltage noise from the inverter
   cannot cause interfere through this connection.
 - A Charge‐Pump signal is provided. This helps the user to form a safety interlock condition among
   controller and devices.
 - 22 isolated input terminals, consisting of 17 terminals of NPN and 5 terminals of PNP type.
 - 14 NPN isolated output terminals capable of sinking current up to 100mA for each channel and up to
   500mA per group.
 - New! MB2v1.5, 2 onboard relays with both NO / NC contacts and “Off Delay Time”, which can be
   used for “Z Drop Protection” application. (MB2v1.3 does not have this feature)

I ordered an MB2 a few weeks ago, and it's hands down the most professional looking breakout board I've ever seen. It's also the cheapest way to get 3 ports of I/O in a single board solution.
While it's designed to be used with an ESS, I'm using it with a UC300ETH with a minor mod, removing the wire to pin26 in the ribbon cables.

Everyone will probably have a different opinion based on their experience, likes and dislikes but my money would be on the CNC4PC type C11 board. http://www.cnc4pc.com/Store/osc/product_info.php?products_id=161

Tweakie.

Hi Tweekie,

I'm back after a long spell away, hopefully you will not objectto my direct question.

I have ESS Smooth stepper with CM106 BOB.
When wiring the stepper drives I have connected Pulse - and Dir - to the Axis output on the CM106. I'm confused with the Pulse + and Dir + because on my previous board I hooked these up to 5Vdc.  Do I do the same for the CM106 ??

Regards

George

Hi George,

The CM106 has connections for Pul+, Dir+, Pul-, Dir- and that’s where they should be connected.

Tweakie.