Archive for April, 2011
After completing the first revision of the uIEC/SD daughtercard, I grew unsatisfied with with the sole but significant shortcoming. In all applications except the C128DCR usage, the dual IEC connectors would obscure some important port of the host machine. On the VIC/C64/C64C, the connectors would prevent user port usage, while C128/C128D applications would affect video and IEC connector usage. With so many machine types affected, there was little reason to include a cassette port connector, since many of the uses would require a USB power supply. Removing the cassette port connector would create two issues: Comments Off on uIEC/SD Daughtercard modifications more...
- The unit would cost more to produce and sell (mandatory USB power supply).
- Complexity would be increased (additional power supply to attach, additional power connection required, additional item to remember when packing unit for travel).
- IEC ports no longer restrict access to C128, C128D, VIC-20,C64, or C64C owners.
- Many owners never enclose the unit. The new revision puts the unit behind the machine and physically attaches the unit to the machine, minimizing the need for an enclosure.
- The few that do mount in an enclosure appear savvy enough to construct an extension for the uIEC/SD connector or determine an alternate connection method.
With the next batch of uIEC/SD units, I found both financial and feature-enhancement reasons to redesign the connector daughterboard. Compared to the earlier daughtercard option, there are some key advantages to the new unit: Comments Off on uIEC/SD Daughterboard Redesign more...
- Dual IEC connectors. No longer much the uIEC/SD be the last unit in the IEC bus chain.
- Onboard RESET button
- Via jumper, Machine reset can optional reset uIEC/SD.
- Better function button access
- Solder pads for all major functions (buttons, PWR, GND)
- No more pigtail power connector
- Mini-USB power supply support
- Significant savings can be realized by utilizing a new IEC jack footprint.
- I am running low on C2NPower PCBs (used for the pigtail) and resupply is not cost effective at present.
- Wiring pigtails takes time, which in turn slows down order fulfillment.
- Some people object to the power pigtail approach.
After a lengthy wait, I am finally finishing the VIC version of the X-Pander3 cartridge expansion system. The design is subject to some more changes, but I am starting to source the required cartridge port connectors needed for the design. The unit shares design elements from the C64 version, but provides maximum flexibility for the VIC-20 owner: Comments Off on X-Pander3, VIC-20 Edition more...
- I/O2 and I/O3 are swappable
- All BLK and RAM signals can be switched
- As with the C64 version, Slot 3 can be vertical or horizontal
- Standoffs to align board with height of expansion port
- All controls are located on right side for ease of access
- The ubiquitous "RESET" switch!