peekb

All good notes. I'll see if I swing back to it after the other projects are out the door and maybe do a full/proper release. Thanks for the feedback!

Thanks for the nice words and creating a thread! I'm not the best at PR and marketing. Your comment on difficulty plateauing couldn't be more accurate. There are technically 7 levels. After level 7 the difficulty stops progressing and stays at that rate. It is probably too easy. I'll see if I can tweak that in the next version. That said, I'm not working on new features or expanding Grogger beyond bug fixes and tweaks...I'm trying to get a few other Lynx things out the door that have been in the queue for quite some time. I'll post more details on one of those things soon (I hope). In the meantime, sincere thanks on the above! I'll try to post here and Discord if/when there are additional updates to Grogger.

Thank you for the very kind words!

For clarification, would "monetizing our brand" include selling a homebrew title with an Atari/Jaguar/Lynx/etc. logo on the box/manual/etc.?

So...the jam started...what are the full details?

To the imxrt/Teensy. I'm only ever sending ROM data to the device. This isn't a Lynx-specific thing, I'm just wanting to "emulate" an EPROM. You can use several of the GPIO pins as virtual serial ports. You only need gnd and rx pins. For my usage, easier than dealing with Ethernet. Direct USB is what I'm using now, however this is where the power situation. You'd have to decouple USB power from the data transmission via USB. For me, the easiest way to do that was via serial. <shrug>

I think my schematic is newer than what my list spin was. I don't have them tied together in the original version, but added it later. I'm not convinced it's the right thing, either. That said, I can power my Lynx + this hardware from my USB port, which makes it pretty seamless. Next version will probably have a jumper on the VCC<->USB power so one can easily enable/disable. And a header to send data via serial with an RS232<->USB adapter, like an FTDI breakout board. I've bodged that up on my current PCB but will make it more official in the next update. Remember, as I said in the first post, I have no idea what I'm doing. I'm just making something that works for me.

Yes, exactly that. 😀

Doubts about what? As for 5V, according to https://www.pjrc.com/store/teensy41.html and the datasheet, no, hence the HC245s.

PDF Schematic posted here: https://github.com/BrianPeek/EPROMEmu/blob/master/schematic/epromemu.pdf

HC245 handles the voltage conversion to/from 5V/3.3V. It also is a tri-state buffer, which allows me to Z-state the data pins on the "EPROM" when CE/OE isn't set. I'll get a PNG/PDF schematic up this week, I was out of town all last week.

Thanks! And again, thank you for the idea. I, too, started with breadboard/soldering nightmare, but I just couldn't keep everything straight and working. The PCB worked the first time out and was far more stable.

With the huge caveat of "I have no idea what I'm doing", I was able to take sage's original idea and build out a simple EPROM emulator using a Teensy 4.1. I open sourced it here: https://github.com/BrianPeek/EPROMEmu Again, and I can't stress this enough, I have no idea what I'm doing. I'm not a hardware guy. But, this hardware, plugged into an old Lynx EPROM cart I had works 100%. I've also used it with a Game Gear and Vectrex EPROM cart, so it's not completely the wrong approach. Adding a wire from the cart's VCC to the power supply of the Teensy allows me to power the Lynx from the USB cable connected to the PC, which is nice. I'll probably add a jumper or something to a future revision. I also ended up adding a quick Reset button to the Lynx so I can quickly upload and reset the console to see the results. Anyway. YMMV, very much a "works for me" project, but thought I'd share since this is where the idea started for me. Thanks!

Which microcontroller are you using for this? I've toyed with this idea for various systems but wasn't sure any uC would be able to toggle GPIO pins fast enough to actually emulate (EP)ROM speeds.

Just came over here to ask if this could be PR'ed to the mainstream cc65. Would love to see these awesome changes make their way into the main cc65 repo. Happy to do the work if it's helpful! Thanks for all of your efforts, karri!