Zarchos wrote:I do not know if it is possible with your board (if the FPGA is 'only' for the CPU, I doubt it. What would be needed is that the FPGA also includes the graphics and memory controller of the QL. This way, I believe, additional features could be added).
As I wrote earlier in this same thread, the Q68 FPGA also contains a graphics controller with QL and Q60 modes, an SDRAM controller, the QL system core, two PS/2 controllers, serial port, sampled sound device, two SDHC card controllers, ROM, fast RAM, extension bus controller. All this was designed by me, so in principle I could add whatever I want, as long as the chip has enough space.
Zarchos wrote:Also, in the case of a linear (ie chunky) screen mode, an additional instruction to load from memory, perform a bit clear operation with the mask equivalent of the value you want to store on screen (ie the data composing the sprite), the ORRing of this 'mask cleared' background with the contents of the sprite you want to display, and finally the storing of the result to memory, could make the whole process faster than th sequence of 68000 instructions to perform all the necessary steps.
It would help to fast plot sprites on screen (for the edges, where the contents of the memory composing the background on screen has to be preserved) and also to fast plot horizontal segments on screen (again for the edges, where the contents of the memory composing the background on screen has to be preserved).
Instead of such specific hardware accelleration, which requires drivers and software we don't have for the QL, I'd rather add CPU cache someday, and/or use higher speed grade chips.
Overall that would be likely to end up with larger speed gain. (This is not an announcement.)
Zarchos wrote:As far as the 'normal' QL is concerned, I already came here to post that, to me, you should pay attention to TerribleFire's (ie Stephen Leary) open source FPGA accelerator board for the Amiga and ST : to me, this project is a perfect condidate to boosting the original QLs.
Could you provide a specific link? At first sight, TerribleFire looks like an Amiga specific 68020 board, in which case a SuperGoldCard remake or one of Nasta/Dave's projects seem more suitable.