rSl
tealifted
- Joined
- Nov 19, 2005
- Messages
- 1,141
just found this little gem. i'm not using my rpi actively right now, but it sounds promising...
"a bare metal port of VICE (x64) for the Raspberry Pi called BMC64. You get true 50hz/60hz smooth scrolling (no horizontal tearing!), low input to audio/video latency and better audio/video synchronization.
What do you mean by bare metal?
There is no operating system! An O/S like Linux adds layers of abstraction between the application (VICE) and the privileged kernel code that has access to hardware. That adds latency in processing events. User space programs can't get notified directly from interrupts, for example. The interrupt has to be serviced by the kernel, into user space, into your program (at the mercy of the scheduler) before they can get processed. For sound production, the user space program must fill buffers to deliver to a sound driver in the kernel before it can pass it on to the hardware. With Combian/PiLizard and Chameleon installations, you are effectively installing a full blown linux distribution (1.5Gb image files!).
With BMC64, VICE -IS- the kernel and has direct access to the hardware. As soon as you power on the device, it goes straight into the emulator. The entire kernel is ~2MB."
announcement and code here
"a bare metal port of VICE (x64) for the Raspberry Pi called BMC64. You get true 50hz/60hz smooth scrolling (no horizontal tearing!), low input to audio/video latency and better audio/video synchronization.
What do you mean by bare metal?
There is no operating system! An O/S like Linux adds layers of abstraction between the application (VICE) and the privileged kernel code that has access to hardware. That adds latency in processing events. User space programs can't get notified directly from interrupts, for example. The interrupt has to be serviced by the kernel, into user space, into your program (at the mercy of the scheduler) before they can get processed. For sound production, the user space program must fill buffers to deliver to a sound driver in the kernel before it can pass it on to the hardware. With Combian/PiLizard and Chameleon installations, you are effectively installing a full blown linux distribution (1.5Gb image files!).
With BMC64, VICE -IS- the kernel and has direct access to the hardware. As soon as you power on the device, it goes straight into the emulator. The entire kernel is ~2MB."
announcement and code here