The Commodore Amiga was a personal computer that replaced the well-loved Commodore 64 in the Commodore product line. It also was one of the many 68K-based personal computers that showed that this CPU was a powerhouse when integrated with additional great hardware.
This is based on the MiSTer Github of the Amiga MiST project (Also known as Minimig) and the VexRISCV RISC-V chip for the Media Processing Unit (MPU) between the core and APF framework for floppy, hard drive and CD-ROM access.
This core works best with the AmigaVision configurations.
Will only work on Analogue OS firmware 2.1 and now works with the default AmigaVision harddrive image, no Pocket-specific version required anymore!
Support for >4GB hard drive images LBA48 has been turned on in the MPU and Analogue Firmware and the data.json file now has this as the MegaAGS.hdf as the default hard drive image to load.
If you are upgrading from an earlier version of the Amiga core with AmigaVision installed: MegaAGS-Pocket.hdf is no longer referenced in the data.json file, so if you want to use the smaller setup instead of downloading the full version, just rename the image file. But we recommend getting the full version to have access to all the games and demos.
Both 68000 and 68020 CPUs
Chip memory 512kB, 1MB, 1.5MB and 2MB
Slow memory none, 512kB, 1MB, 1.5MB
Fast memory of none/2/4/8MB for the 68000 CPU
Fast memory of 16/32MB for the 68020 CPU setup
AGA Chipset
Turbo boot
LBA48 enabled - It can read and write to ADF disk images (floppy disks) up to 2Tbytes now!
Can also access up to 4 Harddrive HDF files
Place your ADF and HDF images in the \Assets\amiga\common folder.
Place the Kickstart BIOS rom in the \Assets\amiga\common folder (Any original 256/512/1024kB firmware ROM will work - no encrypted BIOSes yet). Currently MegaAGS-Kickstart.rom is the default rom
Make sure that the \Assets\amiga\Mazamars312.Amiga\ Folder has the amiga_mpu_bios.bin file - this is supplied and should already be there.
When changing system configurations, you must select the "CPU reset" in the menu to apply the config.
All harddrive and floppy images are to be placed into the \Assets\amiga\common
For harddrive images - In the \Cores\Mazamars312.Amiga\ folder, the data.json file would need to be edited with the files names for each HDF file placed in data slots 310-313. By default, the AmigaVision images are referenced, but you can change the names for other hard drives. These cannot be changed on the fly due to how the HDF images work in the core. They are now limited to 2TB drives. Anything larger will need different sector sizes to run.
If HDD3 or HDD4 are needed make sure your Kickstart has been patched to support this, or install AtapiMagic/IDEFix97. This is not a Pocket Core/MPU issue, but a limitation of AmigaOS from back in the day.
For this you are required to have the following 3 files to place in to the \Assets\amiga\common folder
The Kickstart ROM - MegaAGS-Kickstart.rom
The Main Hard drive image - MegaAGS.hdf
The Save Hard drive image - MegaAGS-Saves.hdf
The recommended settings in the interact menu are as follows:
FDD/HDD LED = Off
Port 1/Port 2 = Mouse/CD32PAD
Mouse Speed = 10
System Config = AGA/Turbo/PAL
CPU Type 68020 CPU - No Cache
memory - Chip = 2Mb
memory - Slow = None
memory - Fast = 32Mbytes
Audio Filter = A500/PWM
Audio Mix = 50%
These can also be defaulted by selecting "Reset all to Default" in the interaction menu
Yes, as you can then fully use the keyboard and mouse to interface with the core. Just make sure you select Port1/Port2 as Mouse/Joystick1 or Mouse/CD32 when using the real mouse (The new APF firmware has been found to have a bug with the mouse plugged in - am awaiting for an update on this).
Also the mouse is emulated on the left analogue thumb stick at the same time as joypad 1 is being used
Be aware that you will need a controller to access the Menu if you want to make changes.
The mouse needs some more work on the clamping and timing for it to work with every mouse. The current mouse I have is a lower sensitivity mouse and I find that it works fine, but high res based mice will cause the mouse to fly off in random locations. Work will be done more once the MPU has some resources changed in it
Have fixed up the Mouse input when a joystick was connected to the dock after has been release on the pocket firmware.
Load Bios - This will allow you to reload new BIOSes on the fly - will cause a reset.
Load Floppy Drive 0-1 - This will allow you to load different floppies while playing. Yes I had to drop this down as there was not enough space in the menus
CPU Reset - This will reset the core, and any change in settings will be applied.
FDD/HDD LED - this places a FDD or HDD activity light on the screen. The HDD light stays on some times unknown why yet.
Floppy Drives - this will allow you to select how many drives are installed, and delimit the transfer rate of the Amiga core.
Port 1/Port 2 - This allows you to change and swap the controller ports with CD32/Normal Joysticks/Mouse - if you need to use the emulated mouse, make sure you use the mouse/joystick or mouse/CD32 options.
Mouse Speed - This will change the update rate of both the emulated and real mouse movements.
Screen Movement X/Y - Moves the screen around.
System Config - Allows you to select PAL/NTSC refresh, OG (original) hardware or the AGA (Advanced Graphics Architecture) hardware, Turbo Boot or standard boot modes.
CPU Type - Allows you which type of CPU you want installed 68000, 68010, 68020 with no cache, 68020 with cache.
Memory: Chip - Size of the Chip memory.
Memory: Slow - Size of the slow memory.
Memory: Fast - on the 68000 and 68010 CPU this is none/2/4/8MB, on the 68020 this is 16 or 32.
Audio Filter: there are 4 options - A500 or A1200 filters with or without PWM
Audio Mixer: This will mix the left and right audio streams together. This defaults to 50%
Yes, you can toggle this with the start button, and the D-pad becomes the movement, and the buttons are emulated on the left and right triggers.
Please note that you need to have the Port1/Port2 setup as Mouse/Joystick1 or Mouse/CD32 for the mouse to work.
Specs:
Running at 74.2MHz (Same as the APF bus).
Connected to the core via a 16bit HPS Bus.
Two timers - one for interrupts and the other for user timing.
Currently, 128KB of memory/RAM for the MPU's program and buffers
Work on interrupts and using a PSRAM chip is needed on the next steps
Current the standard Amiga resolutions for both the OCS and AGA work. Special ECS resolutions like 1024x200 or 1024x400 will not, since the max resolution of the Analogue Pocket is 800x720.
Due to memory access, the RTG resolutions will not work on this right now. They are also not used in the AmigaVision list of games
A few games only work from ADF floppy images with the exact correct version of Kickstart.
The main goal of this project was getting an MPU Framework so external media can be accessed, and help giving developers some tools to help create more cores on the Pocket.
I do expect that there is more to learn about the Amiga to get many of these bugs resolved.
For multi-disk games, also try putting disks in other drives. Make sure you change the amount of installed drives to the amount needed. (Up to 2)
Found that the ICACHE system in the core was causing re-reads while a DMA was happening. Have corrected this and now the AmigaVision games work as well as they do on MiSTer.
The Amiga Vision requires a 68020 CPU, AGA Chipset and extra memory to run. Make sure you do a "Reset all to Default" to get the core to boot.
ICACHE Fixed for WDLOADER to work correctly
LBA48 added to support larger HDD images to 2TB in size
The joysticks are completely disabled when using the emulated mouse or keyboard
Audio Mixing - Still some work to be done here to get rid of the snap or pops from the lower frequencies to 48kHz
Some changes to the caching for the MPU to speed up some processes
Just getting the mouse working on the dock
Thanks to Analogue fixing up the line bug that was found with this core on the dock.
Hard Drive support for the Pocket
Proper 640x400/200 video outputs work!
Write to floppy images
More memory for the fast memory locations and tested working correctly.
Larger memory footprint for the MPU to hold all this awesomeness!!! 128KBYTE OF POWER!
A OSD Keyboard on the pocket when you are playing on pocket mode.
Null modem support using a Gameboy serial cable between two pockets! This could also open up MIDI support.
Also a emulated mouse on a analogue joystick in docked mode (This is the left thumb stick and the left and right triggers for the mouse clicks)
Dropped the floppy drives from 4 to 2 as there was not enough room in the interation menu at this moment.
Interlace mode corrected for games like DarkSeed.
Folder names changed for Unix/Linux/Mac OS and to help with the uploader system.
Faster floppy access times using a larger buffer in the MPU core and caching.
But what about the things below? I wanted to sort out these key issues out first and I'm awaiting a bugfix from Analogue to be released. This is due to files being corrupted when writing back to disk.
Clock input for the Amiga to keep its time.
I have to find out why swapping disks will not always work.
This source code is based on Rok Krajnc project (minimig-de1).
Original Minimig sources from Dennis van Weeren with updates by Jakub Bednarski are published on Google Code and the Community.
The AmigaVision team - Limi, Optiroc and hitm4n for their help and insight into the Amiga, and helping debug the Pocket at the same time with me.
ARM firmware updates and minimig-tc64 port changes by Christian Vogelsang (minimig_tc64) and A.M. Robinson (minimig_tc64).
MiSTer project by Sorgelig (MiSTer) and the Community.
TG68K.C core by Tobias Gubener.
VexRISCV Team - https://github.com/SpinalHDL/VexRiscv
Boogerman for some coding questions - You still owe me on the use of my JTAG tho LOL.
Electron Ash, AGG23 as a beta tester.
Terminator2k2 for his fantastic images for the bootup.
And many more, so please message me and I would happily add you to this if I forgot you!