Hi everybody,
in this posting I wrote that I am not very satisfied with the current implementation of the DM65PIC-Widgetboard. In my opinion the board could be improved in many ways.
I would like to do a revision of the DM65PIC-Widgetboard, but I am very unsure, whether a revision would make sense at all. Here in the forum there are only a few users that have already built this board and there is maybe no need for an improved one. Furthermore in a few months there will be a finalized and ready-to-use MEGA65 to be bought and this would bring the request for a DM65PIC-Widgetboard down to zero I guess.
However I would like to highlight a few improvements of the DM65PIC-Widgetboard that I would like to do:
1) CAD-System would be KiCAD instead of EAGLE
This would be mandatory because I switched to KiCAD a few years ago.
2) Improvement of Circuit Diagram
I would like to draw a "function-based" circuit diagram. As an example the circuit drawing would be more readable if you group STM32-pins in the STM32-symbol for a specific function together (e.g. interface to the Nexys-Board), instead of having them in line according to their pin-number.
3) Board-Dimensions
I would like to mount the DM65PIC-Widgetboard right under the Nexys-Board. Therefore I would suggest to have exactly the same dimensions of the PCB as the Nexys-Board.
4) Mounting-Holes
With four mounting holes at each corner the DM65PIC-Widgetboard could be screwed either under the Nexys-Board or to any other base plate.
5) Same Component Size
For your convenience I would not go with smaller components for resistors and capacitors. I would prefer to use the same size (0805) for them so that one can easily solder them onto the PCB.
6) Same Component References
I would like to use the same component designators as on the original board as far as possible, so that equal functions will have the same component references. (E.g. SV2 would be the C65 keyboard connector on both the original and the improved PCB)
7) Global Silkscreen Improvement
I would like to do a massive improvement of the silkscreen on both sides, so that you can at least easily identify each component.
8 ) Additional IEC-Interface
Would it be an improvement, if an IEC-Interface for an external floppydrive would be included onto the PCB? I do not know anything about it yet, but if there will be a board revision and if an IEC-Interface would be requested then if would be the right time to include one...
9) Using components that are easy available
At the moment the Widgetboard contains components (e.g. On/Off-Switch, Battery-Holder) with no part-number, so that these components are difficult to buy. I would like to have a bill of material where all the components are listed and furthermore where the purchase order number of Reichelt, Mouser, Digikey and LCSC are included. With that information it would be very easy to buy all the components.
Of course, all design files would be uploaded to my github pages and would be open-source.
What do you think? What is your opinion on this topic? Do you have any other suggestions or should I simply stay with the original board and wait for a final MEGA65? I am eager to read your feedback!
Cheers,
Thomas