We got a new loader for the Quickdev16 firmware. The loader will replace
the current dummy loader and has a few new advantages:
Faster upload because of IRQ driven communication between SNES and AVR
Progressbar while uploading
Display Rom infos
ASCII and Katakana font support
Eyecandy: new logo design with sine wave effect and bassdrum synced
Due to these features the loader blew up to more than 55kb, too much for
our limited space in the AVR progmem (64kb – 4kb bootloader). Our main
firmware is between 8kb and 24kb, depends on the debug-features that you
compile in. So the recent task is to either reduce the loader size by
skipping eyecandy, finding a better compression routine to compress it
in the progmem or build a minimal firmware and put parts of the loader
into the surplus 4kb eeprom on the AVR. Probably we will have to combine
the different approaches.
One reason why the firmware is that big these days is the new “minimal
debug terminal”, a serial command line where you can maintain the
Quickdev system status. You can dump memory regions from sram, switch
between the busses, write to the shared memory section, show the status
of the hardware ports and use several other usefull commands. Check the
project page for more details on the commands.
Last week we shipped the first batch of Quickdevs. The Software is feature ready, but we wanted to do some eye candy on the SNES software side, which didn’t work out yet. So software updates are coming within the next weeks.
Not “out of the box” but with only slightly changes on the software part, the new quickdev16 PCBs are working. Their shape fit the SNES cartslot, the changes in hardware design and parts worked out great and we have a kind of stable firmware and upload tool.
When you turn on the SNES, the microcontroller extracts a small loader-rom into the cartridge RAM that is mapped into the SNES addressspace. This one copies itself to SNES’s WRAM and jumps into it. So the cartridge RAM is unaccessed and we can safely switch back to the AVR mode to push a real payload rom onto the cartridge. We are also working on a shared memory function so that we can use the cartridge RAM
to exchange infomation between the AVR and the SNES. This will be used to display a proper Progressbar
while uploading a rom.
As usal you can use our patched version of ucon64 – even under windows – to upload a game to the quickdev16. When the upload is done, the SNES reset line is pulled by quickdev16 and the game starts. When you press the reset button, you only reset the game, not the quickdev16 – it acts like a normal cart. When you press the reset button during the upload process or while watching the loaderscreen, you reset the quickdev and can abort uploads or just restart the quickdev16 – thats a really usefull feature. To initiate the upload of a new game, just start the upload process with ucon, the quickdev switches to the loader mode by itself and receives the new ROM.
So the steps are now to improve the loader code, finish the progress bar stuff, figure out how to solder the PCBs faster than now and add some minor features. Stay tuned for updates, it’s not too long to the release.
I start taking inoffical pre-orders for the Quickdev16 now. Just send me an email to david at optixx.org with your name and email address. In order of arrival i will put you on the pre-order list. Right now we plan to sell around 35 cartridges.
Why inoffical pre-orders list? A fews points are unclear right now. I don’t know the final price since this will depend on the assembling costs which are not setteld yet. I can’t say if the the new PCB are working 100% since we didn’t test it yet. Also we didn’t figured out if we gonna ship the cartidge with a CIC chip or not.
The client software is tested and developed under Linux and OS X. Can’t say much about windows. But if you can compile ucon64 with libusb support in windows you should be fine. I will give this a shot soon.
These points will clear up within the next 2-3 weeks. But expect an sale price around 100 USD or 80 Euros. I gonna use paypal for international shipping and direct debit in Germany and even Europe. Will provide an an IBAN and paypal account later.
I don’t take any money before everything has clear up. So the pre-order is not binding as long as you are not happy with the final outcome of the project. I just started this pre-order list, since a few people start asking for it and they don’t want to miss the opportunity to get one.
Things are going well. Have added some features to the software side and also got some stuff working hardware wise.
Can confirm that US/JAP roms are working.Only tested EU roms before. Used my japanese Nintendo junior and a japanese CIC to confirm that the snesram is working with that setup too.
Max and i added an bootloader to the AVR software toolchain. Now its possible to flash the AVR firmware via the same USB cable as for the normal bulk transfer. So no extra ISP programmer is needed to change the AVR firmware. This is super fast, can flash the 16kb client side firmware in like 3 secs.
Added a reset line trigger to the snes bus. Now the client software can reset the snes after uploading the software. So its possbile to push a rom via ucon64 from the pc and then reset is done by ucon64 and the firmware. No interaction needed from there.
Max is refactoring the schematics so that we can send them over to the pcb fab soon. Stay tuned.
Max took a quick break from his vacations and was able to work on the new hardware revision of the snesram. Its mainly a bugfix to version 0.1 . We also did some cost reductions. Most obvious is to go for 2 Mbyte of sram instead of 4Mbyte. It just make the PCB smaller and less complex. I guess this should be alright with most peoples needs.
We gonna print a small amount of PCB and will take pre-orders as soon as we know they will arrive. Not sure about the final price, depends on the PCB costs and if we get
better prices for the sram. Stay tuned.
Changes in Detail:
* Add AVR reset button
* Fix CS bug and add additional gate
* Reduce to 2 Mbytes for 16 Mbits games
* Snes reset line trigger
* No FTDI for the serial line
* Add RX/TX to pin header
* Model Snes connector header
* 1,2 mm PCB for direct plug
* Blacksolder Mask
* White silk screen