Commit History

Author SHA1 Message Date
  bartpleiter 9438941e15 Initial setup to simulate 100mhz cpu in verilog testbench. 6 months ago
  bart da2bff2ea2 Removed/disabled NTSC from design, as the tiny HDMI monitor is practically always used. Also greatly increased L2 cache size, although no performance benefits for the relatively small programs I currently use for benchmarking. 1 year ago
  bart 2287e54c6b Integrated valid bits into cache block ram. Reset now iteratively clears the entire cache. Allows for much lower FPGA usage and better timings. Should be able to greatly increase cache size as there is an abundance of BRAM. 1 year ago
  bart 88681ec5d0 New arbiter that further improves performance by removing latency for instruction memory access. Created instability again, which I found to be caused by bad interrupt timings. Fixed by changing the interruptValid wire to use branch_MEM for alignment. I do not know why this fixed all problems as it is very hard to simulate this issue. L1 cache should be possible again! 1 year ago
  bart add43b75da L2 cache at 100MHz now greatly increases performance. Attempted to create l1i and l1d cache, but becomes unstable and the issue is difficult to similate/replicate. Therefore, all l1 cache is now bypassed and the code can be found in l1cacheUnstable.v. As no l1 cache anymore, I removed some ccache statements to increase performance as this instruction currently does nothing. 1 year ago
  bart 7e81e7fa17 Added files missing from last commit (L1I cache). 1 year ago
  bart dfb3bbb48e Added L1D cache. Currently only works stable when valid bit is set 0 on WRITE. Valid bit 1 after cache miss read works fine for some reason. 1 year ago
  bart b6831c4209 Added L2 cache (no L1 for now) between CPU and SDRAM controller. No noticable performance difference, can likely be optimized further to reduce cache hit latency. 1 year ago
  bart 28bcde6466 New SDRAM controller that uses both SDRAM chips. Now separate bus from MU for better performance, as controller runs at 100MHz. Also updated some debug code as debugging was needed. Tested working in hardware. 2x performance boost in some cases. 1 year ago
  bart 9f74a9565f Fixed more MU I/O bugs. Updated everything from BCC except the ASM to work on new CPU. Added back flasher programs. Fixed LOAD/HI bug by using unsigned const16 instead. Updated assembler including hotfix for FPGC jumping to addr3 after UART bootloader is done. FPGC6 now basically fully works again! 2 years ago
  bart 207413dd90 Assembler only needs Int: function, fixed position of program lenght. Ported ROM and UART bootloader over from FPGC5. Updated documentation on interrupts. Added resets. Fixed bug in MU. Increased stack size. Tested everything in hardware. Probably some other fixes and things I forgot. 2 years ago
  bart baff95d710 Regbank and stack are now placed in BRAM, fixed combinational loop but further testing needed. 2 years ago
  bart b74702c915 Created full FPGC6 verilog simulation, added Quartus code from FPGC5 with CPU from FPGC6. Works in hardware, but has combination loop somewhere at the arbiter and the registerbank and stack are not using block ram 2 years ago