Last year I created my own rendition of the SD2IEC, dubbed the SD2IEC Pluggable. Version 1.0 left some room for improvement and recently I found the time to take on a new revision. Version 2.0 is even closer related to the design published by Shadowolf while maintaining the “pluggable” layout with the pass-through tape connector.
Most notably, the size of the PCB has been reduced by more than 50%. To achieve this, the SD slot has been replaced by the micro variant and the external USB power supply option was ditched. The components for the intended Tapuino integration — which never came to be — are gone, too.
Instead, there are new breakout connectors that were previously missing, giving access to pins for connecting external LEDs, disk switch buttons, an LCD daughter board, and device id selection. Here is the bill of materials:
|1||XS1||Micro SD Slot||eBay|
|1||J4||6 pin DIN socket||eBay|
|2||C1-2||56pF capacitor 0805||eBay (China) eBay (Germany)|
|3||C3-5||10µF tantalum capacitor 3216||eBay|
|2||C6-7||100nF capacitor 0805||eBay|
|1||D1||LED 0805 red||eBay|
|1||D2||LED 0805 green||“|
|2||R1,R5||0805 resistor 330Ω|
|4||R2,R6,R9,R12||0805 resistor 18Ω|
|4||R3,R7,R10,R13||0805 resistor 10kΩ|
|4||R4,R8,R11,R14||0805 resistor 22kΩ|
|1||R15||0805 resistor 2.2Ω|
|2||SW1,SW2||SMD push button 3x6mm||eBay|
|1||U1||ATMega644-20AU or ATMega1284||eBay eBay|
|1||U2||AMS1117-3.3 voltage regulator||eBay|
|1||Y1||HC49 crystal 8MHz||eBay|
Once the new version has been sufficiently tested and if everything seems to work, the project files will again be freely available.
Update 1: While it is generally working fine, there are a few minor issues in version 2.0 that I will address:
- The numbering of LED 1 and 2 has accidentally been swapped.
- There should be some more space between the data lines and the zip tie drill holes to give some leeway for less-than-accurate manufacturing.
- Speaking of zip tie holes: they could be a little bigger.
- The ground plane and the solder mask layer around the edge connection fingers could be placed better.
Update 2: Finally, after enough people kept nagging me, I managed to clean up the repository. So, the KiCAD project files are again available on Github in case you’d like to make your own pluggable SD2IEC. If you do, I would love to hear about it in the comments!