Denial

I interpreted the doc as saying "this would support 1MB (of RAM or ROM) if it was connected" (i.e. with no changes to the CPLD). But it'd be impossible to say without trying it. I don't see what the additional address line would be connected to with the existing image. I think I've manage...

So, your assumption sounds correct, Srowe. It seems like the 512k choice was completely a consequence of the DIL choice...so maybe bumping up the spec to 1MB is free after all? :) I've put looking at expanding to 1MB on the back burner for now. The available footprints don't look too friendly for h...

Actually it would be nice to be able to mute the memory expansion and still have the SD card reader; if that even works with one of those expansion port quadruplers plus, well, Ultimem... That's possible today, flip DIP switch 3. Disables access to BLK5 and therefore the CPLD isn't programmed to en...

Still tinkering with the overall layout. The cartridge shells arrived, I think the LEDs and switches are going to work better on the main face rather than the top edge. I've also added an ISP header for the ATMega, that will make it easier to initially program it.

Do all bits have to be set for serial and clock out or is one bit sufficient? You'll need to read and understand the 6522 datasheet. Register $C is the Peripheral Control Register (PCR). Those three bits act together to control what happens to CB2, whether is is an input or output etc. As it is con...

my 3 x FE3s, all have crosstalk issues, I can't run 35k programs with them... :? You should be able to fix that, but it requires soldering a wire and reprogramming the CPLD (which needs a JTAG programmer). I need to write up the BoM to get an idea of what the new cart will cost, I'm hoping that I'l...

I've got a tentative layout of the PCB
I might need to move some of the smaller components around to reduce the length of traces but I think the major ones are in about the right place. I've got some cartridge shells on order, the LEDs and buttons might need adjustment too.

Out of curiosity, does anyone use a WiFi adapter or something to transfer files to/from their Vic? Or USB (does that even exist)? I'm not using anything more elaborate than SD card swapping myself, but it feels like maybe the real issue here is that whole process. I'm guessing that FujiNet might be...

Yeah, it's a bit of a bug-bear for me. IMO SD-cards were pretty much the perfect size for a whole range of applications, but technology is what it is. Perhaps a poll would be a more democratic way of deciding which way to go? :-? Full-size cards are easier to handle, I agree. I think I'll revert to...

Is it possible to install an IEEE extension that can access a second 6502 processor. Can be used almost like a FLoppy but of course without the mechanics and "only" equipped with RAM and ROM. RAM = 64kbyte; ROM 4kbyte? Sounds like your looking for an emulated storage serial bus device? I'...

Oh please, no! I can (sort of) see the need for smaller-format cards for mobile phone, but for the FE3 a 'full-sized' SD card-slot is better. It will also offer the option to use SD and micro SD cards. MicroSD are just too fiddly... Interesting you feel strongly about this. I'll have a check about ...

Here's the completed schematic FE3ng.png I had to quickly dive into slightly more complex concepts such as creating new symbols as I couldn't find suitable ones for the microSD slot or the RTC chip. After an initial struggle I was able to make up just what I needed quite easily. I found drawing with...

It just needs one more address line out of the CPLD and the firmware tweaking. The price of the larger SRAM looks to be identical to the current chip. In my enormously simplistic understanding of the CPLD code it needs A19 assigning to a spare pin pin 34 = A13; /* EEPROM A13, SRAM A13 */ pin 38 = A...

First of all, love the effort! I think the cross-talk issue stunted some of the excitement around this cartridge (at least it did for me) so it will be amazing to put that behind us. Thanks for the encouragement. I think the FE3 is a great cart, it rolls all the missing functionality (RAM expansion...

As mentioned in another post I'm in the process of designing a refreshed version of the Final Expansion 3 cartridge and thought it may be interesting to others to record my progress here. I'm planning to eventually produce (in limited quantities) complete carts, including case. I'm sure there's a de...