fpga_examples

Example code in vhdl to help starting new projects using FPGA devices.

What is here

Quartus II projects files for the Turbo Chameleon 64 hardware V1. These are located in the quartus/chameleon folder.

• chameleon_example_io. An example demonstrating how to access I/O ports on the Chameleon hardware.
• chameleon_life. Conways game of life implementation for Chameleon. It requires a PS/2 mouse.
• chameleon_v5_hwtest. Chameleon hardware selftest for hardware production and diagnostics.

Quartus II projects files for the Turbo Chameleon 64 hardware V2. These are located in the quartus/chameleon2 folder.

• chameleon2_hwtest. Chameleon hardware selftest for hardware production and diagnostics.
• chameleon2_life. Conways game of life implementation for Chameleon. It requires a PS/2 mouse.

Various vhdl files to be reused in other designs.

• rtl/audio. Support files for processing audio.
  • audio_sigmadelta_dac.vhd, Audio sigmadelta first order 1 bit converter.
• rtl/chameleon. Support files for porting designs to the Turbo Chameleon 64 hardware.
  • chameleon_1khz.vhd, An 1 khz trigger generator (requires 1 mhz trigger input).
  • chameleon_1mhz.vhd, An 1 Mhz trigger generator.
  • chameleon_autofire.vhd, Joystick autofire circuit.
  • chameleon_buttons.vhd, Logic to debounce the three blue buttons on the Chameleon. Detects short and long presses.
  • chameleon_c64_joykeyb.vhd, Logic to readout the C64 keyboard and joystick ports (used by chameleon_io).
  • chameleon_cdtv_remote.vhd, Decoder for the IR signals transmitted by the CDTV remote.
  • chameleon_docking_station.vhd, Decoder for the bitstream generated by the Chameleon docking-station.
  • chameleon_io.vhd, Chameleon timing and I/O driver. Handles all the timing and multiplexing details of the cartridge port and the CPLD mux.
  • chameleon_led.vhd, LED blinking circuit.
  • chameleon_old_sdram.vhd, Example SDRAM controller (has multiple ports of different widths)
  • chameleon_phi_clock_*.vhd, C64 Phi2-clock regeneration and divider. (used by chameleon_io to sync. to PHI2 signal)
  • chameleon_spi_flash.vhd, Read data from on of the slots in the 16 Mbyte SPI serial flash.
  • chameleon_usb.vhd, Logic to allow reading and writing memory through the usb port with chaco. Also supplies the current flash slot.
  • chameleon2_e, Default toplevel entity for Turbo Chameleon 64 second edition.
  • chameleon2_io_ps2iec, Read PS/2 and IEC data from the input multiplexer
  • chameleon2_io_shiftreg, Statemachine to control the output shiftregister for reset lines, PS/2 and LEDs.
  • chameleon2_spi, Chameleon SPI controller for communicating with flash and sdcard on V2 hardware.
• rtl/general. Varios support and example files.
  • gen_bin2gray.vhd, Binary to gray-code converter.
  • gen_button.vhd, Button debouncer
  • gen_counter.vhd, Up/Down counter example.
  • gen_counter_signed.vhd, Up/Down counter that outputs signed value.
  • gen_dualram.vhd
  • gen_fifo.vhd, Single clock domain FIFO buffer, with configurable width and depth.
  • gen_filter.vhd, Signal filter to detect stable digital signal.
  • gen_lfsr.vhd, Linear Feedback Shift Register. Generates pseudo random numbers.
  • gen_pipeline.vhd, Configurable pipeline building block.
  • gen_register.vhd, Register example.
  • gen_reset.vhd, Power-on reset circuit with manual reset button input.
  • gen_uart.vhd, Simple fixed baudrate asynchronous serial receiver/transmitter
  • gen_usart.vhd, Synchronous serial receiver/transmitter
• rtl/ps2. Design files to add support for PS/2 keyboards and PS/2 mice.
  • io_ps2_com.vhd, Lowlevel PS/2 driver. Allowes receiving and sending bytes to PS/2 devices.
  • io_ps2_keyboard.vhd, PS/2 keyboard interface (uses io_ps2_com). Receives scancodes and can control the LEDs.
  • io_ps2_mouse.vhd, PS/2 mouse interface (uses io_ps2_com). Gets position and button information from PS/2 mice.
• rtl/ttl. Files for emulating standard logic chips like SN74xx and CD40xx series in realtime on FPGAs.
  • ttl_74??.vhd, VHDL implementation of various standard logic chips from the 74HCT series.
  • ttl_latency, Lowlevel building block to emulate propagation delays in chips (as an bonus also pipelines designs for easier mapping).
  • ttl_pkg, Package that defines the ttl_t type. A new logic signal type that handles more states as just zero and one.
• rtl/video. Support files for processing video.
  • video_vga_master.vhd, VGA sync. and timing generator.
  • iq_mixer, IQ mixer for PAL/NTSC video. Requires clock exactly 16x faster as color-burst frequency.