The following links are provided “as is” for the possible use of anyone who might wish to avail themselves of the work done to develop this product. Please keep in mind this product development process is still on going. What is presented here is only the the early beta version of this hardware card. We therefore, offer no guarantees for its fitness in any particular application.
While this card assembly has shown itself extremely useful in a variety of applications, it does have some minor issues. Issues that were corrected in subsequent production versions. Most notability among these: is difficulty we had getting the on-board clock to function within accuracy specifications. Second generation cards eliminated the use of external crystal which solved this production problem. However, for many applications the clock is adequate. For instance, PC host software compensates for clock drift by updating the time on board every hour.
Another small problem with the original design was how the keep-alive signal to the RTC was first wired. To make this feature work correctly, there is a procedure for cutting one trace and adding a resistor and a diode to control charging current to a capacitor that serves as the clock battery. For more information on this modification contact me at firstname.lastname@example.org
Here is a link to batchPCB.com where the board was first fabricated. This link should be all one needs to place an order this PCB