| 1 |
105 |
davidgb |
-- SECD Front End Processor derived from System09 written by John E. Kent
|
| 2 |
|
|
-- This core adheres to the GNU public license
|
| 3 |
|
|
|
| 4 |
|
|
library ieee;
|
| 5 |
|
|
use ieee.std_logic_1164.all;
|
| 6 |
|
|
use IEEE.STD_LOGIC_ARITH.ALL;
|
| 7 |
|
|
use IEEE.STD_LOGIC_UNSIGNED.ALL;
|
| 8 |
|
|
use ieee.numeric_std.all;
|
| 9 |
|
|
--use config.all;
|
| 10 |
|
|
|
| 11 |
|
|
entity secd_fep_trenz is
|
| 12 |
|
|
port(
|
| 13 |
|
|
utmi_clkout : in Std_Logic; -- UTMI Clock input
|
| 14 |
|
|
utmi_databus16_8 : out Std_Logic; -- UTMI configuration input
|
| 15 |
|
|
|
| 16 |
|
|
reset_sw : in Std_logic; -- Master Reset input (active low)
|
| 17 |
|
|
|
| 18 |
|
|
-- PS/2 Keyboard
|
| 19 |
|
|
ps2_clk1 : inout Std_logic;
|
| 20 |
|
|
ps2_data1 : inout Std_Logic;
|
| 21 |
|
|
|
| 22 |
|
|
-- Uart Interface
|
| 23 |
|
|
fpga_rxd : in Std_Logic;
|
| 24 |
|
|
fpga_txd : out Std_Logic;
|
| 25 |
|
|
fpga_cts : in Std_Logic;
|
| 26 |
|
|
fpga_rts : out Std_Logic;
|
| 27 |
|
|
|
| 28 |
|
|
-- CRTC output signals
|
| 29 |
|
|
vsync_b : out Std_Logic;
|
| 30 |
|
|
hsync_b : out Std_Logic;
|
| 31 |
|
|
fpga_b : out Std_Logic_Vector(2 downto 0);
|
| 32 |
|
|
fpga_g : out Std_Logic_Vector(2 downto 0);
|
| 33 |
|
|
fpga_r : out Std_Logic_Vector(2 downto 0);
|
| 34 |
|
|
|
| 35 |
|
|
-- LEDS & Switches
|
| 36 |
|
|
mm_led : out Std_Logic;
|
| 37 |
|
|
led : out Std_Logic_Vector(3 downto 0);
|
| 38 |
|
|
|
| 39 |
|
|
joy_down : in Std_Logic;
|
| 40 |
|
|
joy_fire : in Std_Logic;
|
| 41 |
|
|
joy_left : in Std_Logic;
|
| 42 |
|
|
joy_right : in Std_Logic;
|
| 43 |
|
|
joy_up : in Std_Logic;
|
| 44 |
|
|
|
| 45 |
|
|
-- LCD Display
|
| 46 |
|
|
lcd_e : out Std_Logic;
|
| 47 |
|
|
lcd_rw : out Std_Logic;
|
| 48 |
|
|
lcd_rs : out Std_Logic;
|
| 49 |
|
|
lcd_d : out Std_Logic_Vector(3 downto 0);
|
| 50 |
|
|
|
| 51 |
|
|
-- Audio
|
| 52 |
|
|
aud_out : out std_logic_vector(4 downto 1);
|
| 53 |
|
|
|
| 54 |
|
|
-- Memory interface
|
| 55 |
|
|
ram_a : out std_logic_vector(20 downto 1);
|
| 56 |
|
|
ram_io : inout std_logic_vector(15 downto 0);
|
| 57 |
|
|
ram_bhen : out std_logic;
|
| 58 |
|
|
ram_blen : out std_logic;
|
| 59 |
|
|
ram_cen : out std_logic;
|
| 60 |
|
|
ram_oen : out std_logic;
|
| 61 |
|
|
ram_wen : out std_logic;
|
| 62 |
|
|
|
| 63 |
|
|
-- Compact flash
|
| 64 |
|
|
cf_reset : out std_logic;
|
| 65 |
|
|
-- cf_irq : in std_logic;
|
| 66 |
|
|
cf_iord : out std_logic;
|
| 67 |
|
|
cf_iowr : out std_logic;
|
| 68 |
|
|
-- cf_wait : in std_logic;
|
| 69 |
|
|
-- cf_dasp : in std_logic;
|
| 70 |
|
|
-- cf_pdiag : in std_logic;
|
| 71 |
|
|
-- cf_cd1 : in std_logic;
|
| 72 |
|
|
-- cf_cd2 : in std_logic;
|
| 73 |
|
|
-- iois16 : in std_logic;
|
| 74 |
|
|
-- cf_oe : out std_logic;
|
| 75 |
|
|
cf_pwr_en : out std_logic;
|
| 76 |
|
|
cf_cs0 : out std_logic;
|
| 77 |
|
|
cf_cs1 : out std_logic
|
| 78 |
|
|
-- cf_we : out std_logic;
|
| 79 |
|
|
-- cf_rew : out std_logic
|
| 80 |
|
|
);
|
| 81 |
|
|
end secd_fep_trenz;
|
| 82 |
|
|
|
| 83 |
|
|
-------------------------------------------------------------------------------
|
| 84 |
|
|
-- Architecture for System09
|
| 85 |
|
|
-------------------------------------------------------------------------------
|
| 86 |
|
|
architecture rtl of secd_fep_trenz is
|
| 87 |
|
|
-----------------------------------------------------------------------------
|
| 88 |
|
|
-- constants
|
| 89 |
|
|
-----------------------------------------------------------------------------
|
| 90 |
|
|
constant fep_only : integer := 1;
|
| 91 |
|
|
|
| 92 |
|
|
constant SYS_Clock_Frequency : integer := 50000000; -- FPGA System Clock
|
| 93 |
|
|
constant VGA_Clock_Frequency : integer := 25000000; -- VGA Pixel Clock
|
| 94 |
|
|
constant CPU_Clock_Frequency : integer := 12500000; -- CPU Clock
|
| 95 |
|
|
constant BAUD_Rate : integer := 57600; -- Baud Rate
|
| 96 |
|
|
constant ACIA_Clock_Frequency : integer := BAUD_Rate * 16;
|
| 97 |
|
|
|
| 98 |
|
|
-----------------------------------------------------------------------------
|
| 99 |
|
|
-- ChipScope Pro components and signals
|
| 100 |
|
|
-----------------------------------------------------------------------------
|
| 101 |
|
|
|
| 102 |
|
|
-- component icon
|
| 103 |
|
|
-- port(control0 : out std_logic_vector(35 downto 0));
|
| 104 |
|
|
-- end component;
|
| 105 |
|
|
|
| 106 |
|
|
-- component ila
|
| 107 |
|
|
-- port(control : in std_logic_vector(35 downto 0);
|
| 108 |
|
|
-- clk : in std_logic;
|
| 109 |
|
|
-- trig0 : in std_logic_vector(39 downto 0));
|
| 110 |
|
|
-- end component;
|
| 111 |
|
|
|
| 112 |
|
|
-- signal chipscope_control : std_logic_vector(35 downto 0);
|
| 113 |
|
|
-- signal ila_clock : std_logic;
|
| 114 |
|
|
|
| 115 |
|
|
-----------------------------------------------------------------------------
|
| 116 |
|
|
-- Signals
|
| 117 |
|
|
-----------------------------------------------------------------------------
|
| 118 |
|
|
|
| 119 |
|
|
-- Clocks
|
| 120 |
|
|
attribute buffer_type : string;
|
| 121 |
|
|
attribute period : string;
|
| 122 |
|
|
|
| 123 |
|
|
signal vdu_clk : std_logic; -- 25 Mhz
|
| 124 |
|
|
attribute period of vdu_clk : signal is "40 ns";
|
| 125 |
|
|
attribute buffer_type of vdu_clk : signal is "BUFG";
|
| 126 |
|
|
|
| 127 |
|
|
signal cpu_clk : std_logic; -- 12.5 Mhz
|
| 128 |
|
|
attribute buffer_type of cpu_clk : signal is "BUFG";
|
| 129 |
|
|
|
| 130 |
|
|
-- BOOT ROM
|
| 131 |
|
|
signal rom_cs : Std_logic;
|
| 132 |
|
|
signal rom_data_out : Std_Logic_Vector(7 downto 0);
|
| 133 |
|
|
|
| 134 |
|
|
-- RAM
|
| 135 |
|
|
signal user_ram0_cs : std_logic;
|
| 136 |
|
|
signal user_ram0_dout : std_logic_vector(7 downto 0);
|
| 137 |
|
|
signal user_ram1_cs : std_logic;
|
| 138 |
|
|
signal user_ram1_dout : std_logic_vector(7 downto 0);
|
| 139 |
|
|
|
| 140 |
|
|
-- UART Interface signals
|
| 141 |
|
|
signal uart_data_out : Std_Logic_Vector(7 downto 0);
|
| 142 |
|
|
signal uart_cs : Std_Logic;
|
| 143 |
|
|
signal uart_irq : Std_Logic;
|
| 144 |
|
|
signal baudclk : Std_Logic;
|
| 145 |
|
|
signal DCD_n : Std_Logic;
|
| 146 |
|
|
signal RTS_n : Std_Logic;
|
| 147 |
|
|
signal CTS_n : Std_Logic;
|
| 148 |
|
|
|
| 149 |
|
|
-- keyboard port
|
| 150 |
|
|
signal keyboard_data_out : std_logic_vector(7 downto 0);
|
| 151 |
|
|
signal keyboard_cs : std_logic;
|
| 152 |
|
|
signal keyboard_irq : std_logic;
|
| 153 |
|
|
|
| 154 |
|
|
-- CPU Interface signals
|
| 155 |
|
|
signal cpu_rw : std_logic;
|
| 156 |
|
|
signal cpu_vma : std_logic;
|
| 157 |
|
|
signal cpu_halt : std_logic;
|
| 158 |
|
|
signal cpu_hold : std_logic;
|
| 159 |
|
|
signal cpu_firq : std_logic;
|
| 160 |
|
|
signal cpu_irq : std_logic;
|
| 161 |
|
|
signal cpu_nmi : std_logic;
|
| 162 |
|
|
signal cpu_addr : std_logic_vector(15 downto 0);
|
| 163 |
|
|
signal cpu_data_in : std_logic_vector(7 downto 0);
|
| 164 |
|
|
signal cpu_data_out : std_logic_vector(7 downto 0);
|
| 165 |
|
|
|
| 166 |
|
|
-- Compact Flash port
|
| 167 |
|
|
signal cf_data_out : std_logic_vector(7 downto 0);
|
| 168 |
|
|
signal cf_cs : std_logic;
|
| 169 |
|
|
signal cf_rd : std_logic;
|
| 170 |
|
|
signal cf_wr : std_logic;
|
| 171 |
|
|
|
| 172 |
|
|
-- Video Display Unit
|
| 173 |
|
|
signal vdu_cs : std_logic;
|
| 174 |
|
|
signal vdu_data_out : std_logic_vector(7 downto 0);
|
| 175 |
|
|
|
| 176 |
|
|
-- VGA output signals (distributed to VGA DAC)
|
| 177 |
|
|
signal red : std_logic;
|
| 178 |
|
|
signal green : std_logic;
|
| 179 |
|
|
signal blue : std_logic;
|
| 180 |
|
|
|
| 181 |
|
|
-- System Reset (generated by key press)
|
| 182 |
|
|
signal reset : std_logic;
|
| 183 |
|
|
|
| 184 |
|
|
-- LCD register select
|
| 185 |
|
|
signal lcd_cs : std_logic;
|
| 186 |
|
|
|
| 187 |
|
|
-- LED register select
|
| 188 |
|
|
signal led_cs : std_logic;
|
| 189 |
|
|
signal led_reg : std_logic_vector(7 downto 0) := (others => '0');
|
| 190 |
|
|
|
| 191 |
|
|
-- Joystick buffer
|
| 192 |
|
|
signal joystick : std_logic_vector(7 downto 0);
|
| 193 |
|
|
|
| 194 |
|
|
-- LED Flasher
|
| 195 |
|
|
signal blink_count : std_logic_vector(25 downto 0) := (others => '0');
|
| 196 |
|
|
|
| 197 |
|
|
-- SECD interface
|
| 198 |
|
|
signal secd_button : std_logic := '0';
|
| 199 |
|
|
signal secd_stop : std_logic := '1';
|
| 200 |
|
|
signal secd_stopped : std_logic := '1';
|
| 201 |
|
|
signal secd_state : std_logic_vector(1 downto 0);
|
| 202 |
|
|
signal secd_ram_addr_hi : std_logic_vector(7 downto 0) := (others => '0');
|
| 203 |
|
|
signal secd_ram_addr_high_cs : std_logic := '0';
|
| 204 |
|
|
signal secd_ram_cs : std_logic := '0';
|
| 205 |
|
|
signal secd_control_cs : std_logic := '0';
|
| 206 |
|
|
|
| 207 |
|
|
-- SECD RAM Controller interface
|
| 208 |
|
|
signal secd_ram_busy : std_logic;
|
| 209 |
|
|
|
| 210 |
|
|
-- RAM signal taps
|
| 211 |
|
|
signal ram_bhenx : std_logic;
|
| 212 |
|
|
signal ram_blenx : std_logic;
|
| 213 |
|
|
signal ram_cenx : std_logic;
|
| 214 |
|
|
signal ram_oenx : std_logic;
|
| 215 |
|
|
signal ram_wenx : std_logic;
|
| 216 |
|
|
|
| 217 |
|
|
-- Interface signals for SECD
|
| 218 |
|
|
signal secd_ram_din32 : std_logic_vector(31 downto 0);
|
| 219 |
|
|
signal secd_ram_dout32 : std_logic_vector(31 downto 0);
|
| 220 |
|
|
signal secd_ram_addr32 : std_logic_vector(13 downto 0);
|
| 221 |
|
|
signal secd_ram_read32 : std_logic;
|
| 222 |
|
|
signal secd_ram_write32 : std_logic;
|
| 223 |
|
|
|
| 224 |
|
|
-- Interface signals for 6809
|
| 225 |
|
|
signal secd_ram_dout8 : std_logic_vector(7 downto 0);
|
| 226 |
|
|
signal secd_ram_hold : std_logic;
|
| 227 |
|
|
|
| 228 |
|
|
-- Locked signal of clock synthesizer
|
| 229 |
|
|
signal clock_locked : std_logic;
|
| 230 |
|
|
signal ila_clock :std_logic;
|
| 231 |
|
|
-----------------------------------------------------------------
|
| 232 |
|
|
--
|
| 233 |
|
|
-- CPU09 CPU core
|
| 234 |
|
|
--
|
| 235 |
|
|
-----------------------------------------------------------------
|
| 236 |
|
|
|
| 237 |
|
|
component cpu09
|
| 238 |
|
|
port (
|
| 239 |
|
|
clk : in std_logic;
|
| 240 |
|
|
rst : in std_logic;
|
| 241 |
|
|
rw : out std_logic; -- Asynchronous memory interface
|
| 242 |
|
|
vma : out std_logic;
|
| 243 |
|
|
address : out std_logic_vector(15 downto 0);
|
| 244 |
|
|
data_in : in std_logic_vector(7 downto 0);
|
| 245 |
|
|
data_out : out std_logic_vector(7 downto 0);
|
| 246 |
|
|
halt : in std_logic;
|
| 247 |
|
|
hold : in std_logic;
|
| 248 |
|
|
irq : in std_logic;
|
| 249 |
|
|
nmi : in std_logic;
|
| 250 |
|
|
firq : in std_logic
|
| 251 |
|
|
);
|
| 252 |
|
|
end component;
|
| 253 |
|
|
|
| 254 |
|
|
|
| 255 |
|
|
----------------------------------------
|
| 256 |
|
|
--
|
| 257 |
|
|
-- 16KByte Block RAM Mais Forth ROM
|
| 258 |
|
|
--
|
| 259 |
|
|
----------------------------------------
|
| 260 |
|
|
component maisforth_rom_16k
|
| 261 |
|
|
Port (
|
| 262 |
|
|
clk : in std_logic;
|
| 263 |
|
|
rst : in std_logic;
|
| 264 |
|
|
cs : in std_logic;
|
| 265 |
|
|
rw : in std_logic;
|
| 266 |
|
|
addr : in std_logic_vector (13 downto 0);
|
| 267 |
|
|
rdata : out std_logic_vector (7 downto 0);
|
| 268 |
|
|
wdata : in std_logic_vector (7 downto 0)
|
| 269 |
|
|
);
|
| 270 |
|
|
end component;
|
| 271 |
|
|
|
| 272 |
|
|
----------------------------------------
|
| 273 |
|
|
--
|
| 274 |
|
|
-- 8KBytes Block RAM for FLEX9
|
| 275 |
|
|
-- $C000 - $DFFF
|
| 276 |
|
|
--
|
| 277 |
|
|
----------------------------------------
|
| 278 |
|
|
component ram_2k
|
| 279 |
|
|
Port (
|
| 280 |
|
|
clk : in std_logic;
|
| 281 |
|
|
rst : in std_logic;
|
| 282 |
|
|
cs : in std_logic;
|
| 283 |
|
|
rw : in std_logic;
|
| 284 |
|
|
addr : in std_logic_vector (12 downto 0);
|
| 285 |
|
|
rdata : out std_logic_vector (7 downto 0);
|
| 286 |
|
|
wdata : in std_logic_vector (7 downto 0)
|
| 287 |
|
|
);
|
| 288 |
|
|
end component;
|
| 289 |
|
|
|
| 290 |
|
|
-----------------------------------------------------------------
|
| 291 |
|
|
--
|
| 292 |
|
|
-- Open Cores Mini UART
|
| 293 |
|
|
--
|
| 294 |
|
|
-----------------------------------------------------------------
|
| 295 |
|
|
|
| 296 |
|
|
component ACIA_6850
|
| 297 |
|
|
port (
|
| 298 |
|
|
clk : in Std_Logic; -- System Clock
|
| 299 |
|
|
rst : in Std_Logic; -- Reset input (active high)
|
| 300 |
|
|
cs : in Std_Logic; -- miniUART Chip Select
|
| 301 |
|
|
rw : in Std_Logic; -- Read / Not Write
|
| 302 |
|
|
irq : out Std_Logic; -- Interrupt
|
| 303 |
|
|
Addr : in Std_Logic; -- Register Select
|
| 304 |
|
|
DataIn : in Std_Logic_Vector(7 downto 0); -- Data Bus In
|
| 305 |
|
|
DataOut : out Std_Logic_Vector(7 downto 0); -- Data Bus Out
|
| 306 |
|
|
RxC : in Std_Logic; -- Receive Baud Clock
|
| 307 |
|
|
TxC : in Std_Logic; -- Transmit Baud Clock
|
| 308 |
|
|
RxD : in Std_Logic; -- Receive Data
|
| 309 |
|
|
TxD : out Std_Logic; -- Transmit Data
|
| 310 |
|
|
DCD_n : in Std_Logic; -- Data Carrier Detect
|
| 311 |
|
|
CTS_n : in Std_Logic; -- Clear To Send
|
| 312 |
|
|
RTS_n : out Std_Logic -- Request To send
|
| 313 |
|
|
);
|
| 314 |
|
|
end component;
|
| 315 |
|
|
|
| 316 |
|
|
-----------------------------------------------------------------
|
| 317 |
|
|
--
|
| 318 |
|
|
-- ACIA Clock divider
|
| 319 |
|
|
--
|
| 320 |
|
|
-----------------------------------------------------------------
|
| 321 |
|
|
|
| 322 |
|
|
component ACIA_Clock
|
| 323 |
|
|
generic (
|
| 324 |
|
|
SYS_Clock_Frequency : integer := VGA_Clock_Frequency;
|
| 325 |
|
|
ACIA_Clock_Frequency : integer := ACIA_Clock_Frequency
|
| 326 |
|
|
);
|
| 327 |
|
|
port (
|
| 328 |
|
|
clk : in Std_Logic; -- System Clock Input
|
| 329 |
|
|
ACIA_clk : out Std_logic -- ACIA Clock output
|
| 330 |
|
|
);
|
| 331 |
|
|
end component;
|
| 332 |
|
|
|
| 333 |
|
|
|
| 334 |
|
|
----------------------------------------
|
| 335 |
|
|
--
|
| 336 |
|
|
-- PS/2 Keyboard
|
| 337 |
|
|
--
|
| 338 |
|
|
----------------------------------------
|
| 339 |
|
|
|
| 340 |
|
|
component keyboard
|
| 341 |
|
|
generic(
|
| 342 |
|
|
KBD_Clock_Frequency : integer := CPU_Clock_Frequency
|
| 343 |
|
|
);
|
| 344 |
|
|
port(
|
| 345 |
|
|
clk : in std_logic;
|
| 346 |
|
|
rst : in std_logic;
|
| 347 |
|
|
cs : in std_logic;
|
| 348 |
|
|
rw : in std_logic;
|
| 349 |
|
|
addr : in std_logic;
|
| 350 |
|
|
data_in : in std_logic_vector(7 downto 0);
|
| 351 |
|
|
data_out : out std_logic_vector(7 downto 0);
|
| 352 |
|
|
irq : out std_logic;
|
| 353 |
|
|
kbd_clk : inout std_logic;
|
| 354 |
|
|
kbd_data : inout std_logic
|
| 355 |
|
|
);
|
| 356 |
|
|
end component;
|
| 357 |
|
|
|
| 358 |
|
|
----------------------------------------
|
| 359 |
|
|
--
|
| 360 |
|
|
-- Video Display Unit.
|
| 361 |
|
|
--
|
| 362 |
|
|
----------------------------------------
|
| 363 |
|
|
component vdu8
|
| 364 |
|
|
generic(
|
| 365 |
|
|
VDU_CLOCK_FREQUENCY : integer := CPU_Clock_Frequency; -- HZ
|
| 366 |
|
|
VGA_CLOCK_FREQUENCY : integer := VGA_Clock_Frequency; -- HZ
|
| 367 |
|
|
VGA_HOR_CHARS : integer := 80; -- CHARACTERS
|
| 368 |
|
|
VGA_VER_CHARS : integer := 25; -- CHARACTERS
|
| 369 |
|
|
VGA_PIXELS_PER_CHAR : integer := 8; -- PIXELS
|
| 370 |
|
|
VGA_LINES_PER_CHAR : integer := 16; -- LINES
|
| 371 |
|
|
VGA_HOR_BACK_PORCH : integer := 40; -- PIXELS
|
| 372 |
|
|
VGA_HOR_SYNC : integer := 96; -- PIXELS
|
| 373 |
|
|
VGA_HOR_FRONT_PORCH : integer := 24; -- PIXELS
|
| 374 |
|
|
VGA_VER_BACK_PORCH : integer := 13; -- LINES
|
| 375 |
|
|
VGA_VER_SYNC : integer := 1; -- LINES
|
| 376 |
|
|
VGA_VER_FRONT_PORCH : integer := 36 -- LINES
|
| 377 |
|
|
);
|
| 378 |
|
|
port(
|
| 379 |
|
|
-- control register interface
|
| 380 |
|
|
vdu_clk : in std_logic; -- CPU Clock - 12.5MHz
|
| 381 |
|
|
vdu_rst : in std_logic;
|
| 382 |
|
|
vdu_cs : in std_logic;
|
| 383 |
|
|
vdu_rw : in std_logic;
|
| 384 |
|
|
vdu_addr : in std_logic_vector(2 downto 0);
|
| 385 |
|
|
vdu_data_in : in std_logic_vector(7 downto 0);
|
| 386 |
|
|
vdu_data_out : out std_logic_vector(7 downto 0);
|
| 387 |
|
|
|
| 388 |
|
|
-- vga port connections
|
| 389 |
|
|
vga_clk : in std_logic; -- VGA Pixel Clock - 25 MHz
|
| 390 |
|
|
vga_red_o : out std_logic;
|
| 391 |
|
|
vga_green_o : out std_logic;
|
| 392 |
|
|
vga_blue_o : out std_logic;
|
| 393 |
|
|
vga_hsync_o : out std_logic;
|
| 394 |
|
|
vga_vsync_o : out std_logic
|
| 395 |
|
|
);
|
| 396 |
|
|
end component;
|
| 397 |
|
|
|
| 398 |
|
|
begin
|
| 399 |
|
|
|
| 400 |
|
|
-----------------------------------------------------------------
|
| 401 |
|
|
--
|
| 402 |
|
|
-- ChipsScope Pro cores
|
| 403 |
|
|
--
|
| 404 |
|
|
-----------------------------------------------------------------
|
| 405 |
|
|
|
| 406 |
|
|
-- i_icon : icon
|
| 407 |
|
|
-- port map(control0 => chipscope_control);
|
| 408 |
|
|
--
|
| 409 |
|
|
-- i_ila : ila
|
| 410 |
|
|
-- port map(control => chipscope_control,
|
| 411 |
|
|
-- clk => ila_clock,
|
| 412 |
|
|
-- trig0(15 downto 8) => cpu_data_in,
|
| 413 |
|
|
-- trig0(23 downto 16) => cpu_data_out,
|
| 414 |
|
|
-- trig0(39 downto 24) => cpu_addr,
|
| 415 |
|
|
-- trig0(0) => cpu_clk,
|
| 416 |
|
|
-- trig0(1) => cpu_vma,
|
| 417 |
|
|
-- trig0(2) => ram_bhenx,
|
| 418 |
|
|
-- trig0(3) => ram_blenx,
|
| 419 |
|
|
-- trig0(4) => ram_cenx,
|
| 420 |
|
|
-- trig0(5) => ram_oenx,
|
| 421 |
|
|
-- trig0(6) => ram_wenx,
|
| 422 |
|
|
-- trig0(7) => vdu_clk);
|
| 423 |
|
|
|
| 424 |
|
|
-----------------------------------------------------------------
|
| 425 |
|
|
--
|
| 426 |
|
|
-- CPU09 CPU core
|
| 427 |
|
|
--
|
| 428 |
|
|
-----------------------------------------------------------------
|
| 429 |
|
|
|
| 430 |
|
|
my_cpu : entity cpu09 port map (
|
| 431 |
|
|
clk => cpu_clk,
|
| 432 |
|
|
rst => reset,
|
| 433 |
|
|
rw => cpu_rw,
|
| 434 |
|
|
vma => cpu_vma,
|
| 435 |
|
|
address => cpu_addr,
|
| 436 |
|
|
data_in => cpu_data_in,
|
| 437 |
|
|
data_out => cpu_data_out,
|
| 438 |
|
|
halt => cpu_halt,
|
| 439 |
|
|
hold => cpu_hold,
|
| 440 |
|
|
irq => cpu_irq,
|
| 441 |
|
|
nmi => cpu_nmi,
|
| 442 |
|
|
firq => cpu_firq
|
| 443 |
|
|
);
|
| 444 |
|
|
|
| 445 |
|
|
----------------------------------------
|
| 446 |
|
|
--
|
| 447 |
|
|
-- Maisforth ROM (Xilinx Block RAM, 16k)
|
| 448 |
|
|
--
|
| 449 |
|
|
----------------------------------------
|
| 450 |
|
|
|
| 451 |
|
|
my_maisforth_rom_16k : entity maisforth_rom_16k port map (
|
| 452 |
|
|
clk => cpu_clk,
|
| 453 |
|
|
rst => reset,
|
| 454 |
|
|
cs => rom_cs,
|
| 455 |
|
|
rw => '1',
|
| 456 |
|
|
addr => cpu_addr(13 downto 0),
|
| 457 |
|
|
rdata => rom_data_out,
|
| 458 |
|
|
wdata => cpu_data_out
|
| 459 |
|
|
);
|
| 460 |
|
|
|
| 461 |
|
|
-----------------------------------------------------------------------------
|
| 462 |
|
|
--
|
| 463 |
|
|
-- Internal RAM (Xilinx Block RAM, 4k)
|
| 464 |
|
|
--
|
| 465 |
|
|
-----------------------------------------------------------------------------
|
| 466 |
|
|
|
| 467 |
|
|
my_user_ram0_2k : entity ram_2k port map (
|
| 468 |
|
|
clk => cpu_clk,
|
| 469 |
|
|
rst => reset,
|
| 470 |
|
|
cs => user_ram0_cs,
|
| 471 |
|
|
rw => cpu_rw,
|
| 472 |
|
|
addr => cpu_addr(10 downto 0),
|
| 473 |
|
|
rdata => user_ram0_dout,
|
| 474 |
|
|
wdata => cpu_data_out
|
| 475 |
|
|
);
|
| 476 |
|
|
|
| 477 |
|
|
my_user_ram1_2k : entity ram_2k port map (
|
| 478 |
|
|
clk => cpu_clk,
|
| 479 |
|
|
rst => reset,
|
| 480 |
|
|
cs => user_ram1_cs,
|
| 481 |
|
|
rw => cpu_rw,
|
| 482 |
|
|
addr => cpu_addr(10 downto 0),
|
| 483 |
|
|
rdata => user_ram1_dout,
|
| 484 |
|
|
wdata => cpu_data_out
|
| 485 |
|
|
);
|
| 486 |
|
|
|
| 487 |
|
|
-----------------------------------------------------------------
|
| 488 |
|
|
--
|
| 489 |
|
|
-- 6850 ACIA
|
| 490 |
|
|
--
|
| 491 |
|
|
-----------------------------------------------------------------
|
| 492 |
|
|
|
| 493 |
|
|
my_uart : entity acia_6850 port map (
|
| 494 |
|
|
clk => cpu_clk,
|
| 495 |
|
|
rst => reset,
|
| 496 |
|
|
cs => uart_cs,
|
| 497 |
|
|
rw => cpu_rw,
|
| 498 |
|
|
irq => uart_irq,
|
| 499 |
|
|
Addr => cpu_addr(0),
|
| 500 |
|
|
Datain => cpu_data_out,
|
| 501 |
|
|
DataOut => uart_data_out,
|
| 502 |
|
|
RxC => baudclk,
|
| 503 |
|
|
TxC => baudclk,
|
| 504 |
|
|
RxD => fpga_rxd,
|
| 505 |
|
|
TxD => fpga_txd,
|
| 506 |
|
|
DCD_n => dcd_n,
|
| 507 |
|
|
CTS_n => fpga_cts,
|
| 508 |
|
|
RTS_n => fpga_rts
|
| 509 |
|
|
);
|
| 510 |
|
|
|
| 511 |
|
|
|
| 512 |
|
|
----------------------------------------
|
| 513 |
|
|
--
|
| 514 |
|
|
-- PS/2 Keyboard Interface
|
| 515 |
|
|
--
|
| 516 |
|
|
----------------------------------------
|
| 517 |
|
|
my_keyboard : keyboard
|
| 518 |
|
|
generic map (
|
| 519 |
|
|
KBD_Clock_Frequency => CPU_Clock_frequency
|
| 520 |
|
|
)
|
| 521 |
|
|
port map(
|
| 522 |
|
|
clk => cpu_clk,
|
| 523 |
|
|
rst => reset,
|
| 524 |
|
|
cs => keyboard_cs,
|
| 525 |
|
|
rw => cpu_rw,
|
| 526 |
|
|
addr => cpu_addr(0),
|
| 527 |
|
|
data_in => cpu_data_out(7 downto 0),
|
| 528 |
|
|
data_out => keyboard_data_out(7 downto 0),
|
| 529 |
|
|
irq => keyboard_irq,
|
| 530 |
|
|
kbd_clk => ps2_clk1,
|
| 531 |
|
|
kbd_data => ps2_data1
|
| 532 |
|
|
);
|
| 533 |
|
|
|
| 534 |
|
|
----------------------------------------
|
| 535 |
|
|
--
|
| 536 |
|
|
-- Video Display Unit instantiation
|
| 537 |
|
|
--
|
| 538 |
|
|
----------------------------------------
|
| 539 |
|
|
my_vdu : vdu8
|
| 540 |
|
|
generic map(
|
| 541 |
|
|
VDU_CLOCK_FREQUENCY => CPU_Clock_Frequency, -- HZ
|
| 542 |
|
|
VGA_CLOCK_FREQUENCY => VGA_Clock_Frequency, -- HZ
|
| 543 |
|
|
VGA_HOR_CHARS => 80, -- CHARACTERS
|
| 544 |
|
|
VGA_VER_CHARS => 25, -- CHARACTERS
|
| 545 |
|
|
VGA_PIXELS_PER_CHAR => 8, -- PIXELS
|
| 546 |
|
|
VGA_LINES_PER_CHAR => 16, -- LINES
|
| 547 |
|
|
VGA_HOR_BACK_PORCH => 40, -- PIXELS
|
| 548 |
|
|
VGA_HOR_SYNC => 96, -- PIXELS
|
| 549 |
|
|
VGA_HOR_FRONT_PORCH => 24, -- PIXELS
|
| 550 |
|
|
VGA_VER_BACK_PORCH => 13, -- LINES
|
| 551 |
|
|
VGA_VER_SYNC => 1, -- LINES
|
| 552 |
|
|
VGA_VER_FRONT_PORCH => 36 -- LINES
|
| 553 |
|
|
)
|
| 554 |
|
|
port map(
|
| 555 |
|
|
|
| 556 |
|
|
-- Control Registers
|
| 557 |
|
|
vdu_clk => cpu_clk, -- 12.5 MHz System Clock in
|
| 558 |
|
|
vdu_rst => reset,
|
| 559 |
|
|
vdu_cs => vdu_cs,
|
| 560 |
|
|
vdu_rw => cpu_rw,
|
| 561 |
|
|
vdu_addr => cpu_addr(2 downto 0),
|
| 562 |
|
|
vdu_data_in => cpu_data_out,
|
| 563 |
|
|
vdu_data_out => vdu_data_out,
|
| 564 |
|
|
|
| 565 |
|
|
-- vga port connections
|
| 566 |
|
|
vga_clk => vdu_clk, -- 25 MHz VDU pixel clock
|
| 567 |
|
|
vga_red_o => red,
|
| 568 |
|
|
vga_green_o => green,
|
| 569 |
|
|
vga_blue_o => blue,
|
| 570 |
|
|
vga_hsync_o => hsync_b,
|
| 571 |
|
|
vga_vsync_o => vsync_b
|
| 572 |
|
|
);
|
| 573 |
|
|
|
| 574 |
|
|
----------------------------------------
|
| 575 |
|
|
--
|
| 576 |
|
|
-- Clock Synthesis instantiation
|
| 577 |
|
|
--
|
| 578 |
|
|
----------------------------------------
|
| 579 |
|
|
|
| 580 |
|
|
my_clock_synthesis : entity clock_synthesis port map (
|
| 581 |
|
|
clk_30mhz => utmi_clkout,
|
| 582 |
|
|
vdu_clk => vdu_clk,
|
| 583 |
|
|
cpu_clk => cpu_clk,
|
| 584 |
|
|
locked => clock_locked );
|
| 585 |
|
|
-- clk_60mhz => ila_clock);
|
| 586 |
|
|
|
| 587 |
|
|
--make_secd: if fep_only /= '1' generate
|
| 588 |
|
|
-- ----------------------------------------
|
| 589 |
|
|
-- --
|
| 590 |
|
|
-- -- SECD CPU instantiation
|
| 591 |
|
|
-- --
|
| 592 |
|
|
-- ----------------------------------------
|
| 593 |
|
|
--
|
| 594 |
|
|
-- my_secd_system : entity secd_system port map (
|
| 595 |
|
|
-- clk => cpu_clk,
|
| 596 |
|
|
-- reset => reset,
|
| 597 |
|
|
-- button => secd_button,
|
| 598 |
|
|
-- ram_read => secd_ram_read32,
|
| 599 |
|
|
-- ram_in => secd_ram_dout32,
|
| 600 |
|
|
-- ram_write => secd_ram_write32,
|
| 601 |
|
|
-- ram_out => secd_ram_din32,
|
| 602 |
|
|
-- ram_a => secd_ram_addr32,
|
| 603 |
|
|
-- ram_busy => secd_ram_busy,
|
| 604 |
|
|
-- stop_input => secd_stop,
|
| 605 |
|
|
-- stopped => secd_stopped,
|
| 606 |
|
|
-- state => secd_state
|
| 607 |
|
|
-- );
|
| 608 |
|
|
--end generate;
|
| 609 |
|
|
|
| 610 |
|
|
----------------------------------------
|
| 611 |
|
|
--
|
| 612 |
|
|
-- SECD RAM Controller instantiation
|
| 613 |
|
|
--
|
| 614 |
|
|
----------------------------------------
|
| 615 |
|
|
|
| 616 |
|
|
my_secd_ram : entity secd_ram_controller port map (
|
| 617 |
|
|
clk => vdu_clk,
|
| 618 |
|
|
reset => reset,
|
| 619 |
|
|
secd_stopped => secd_stopped,
|
| 620 |
|
|
|
| 621 |
|
|
-- SECD interface
|
| 622 |
|
|
din32 => secd_ram_din32,
|
| 623 |
|
|
dout32 => secd_ram_dout32,
|
| 624 |
|
|
addr32 => secd_ram_addr32,
|
| 625 |
|
|
read32_enable => secd_ram_read32,
|
| 626 |
|
|
write32_enable => secd_ram_write32,
|
| 627 |
|
|
busy32 => secd_ram_busy,
|
| 628 |
|
|
|
| 629 |
|
|
-- 6809 interface
|
| 630 |
|
|
clk8 => cpu_clk,
|
| 631 |
|
|
din8 => cpu_data_out,
|
| 632 |
|
|
dout8 => secd_ram_dout8,
|
| 633 |
|
|
addr8(15 downto 8) => secd_ram_addr_hi,
|
| 634 |
|
|
addr8(7 downto 0) => cpu_addr(7 downto 0),
|
| 635 |
|
|
cs8_ram => secd_ram_cs,
|
| 636 |
|
|
rw8 => cpu_rw,
|
| 637 |
|
|
hold8 => secd_ram_hold,
|
| 638 |
|
|
|
| 639 |
|
|
-- Compact Flash interface
|
| 640 |
|
|
cs8_cf => cf_cs,
|
| 641 |
|
|
|
| 642 |
|
|
-- external interface
|
| 643 |
|
|
ram_oen => ram_oenx,
|
| 644 |
|
|
ram_cen => ram_cenx,
|
| 645 |
|
|
ram_wen => ram_wenx,
|
| 646 |
|
|
ram_io => ram_io,
|
| 647 |
|
|
ram_a => ram_a,
|
| 648 |
|
|
ram_bhen => ram_bhenx,
|
| 649 |
|
|
ram_blen => ram_blenx
|
| 650 |
|
|
);
|
| 651 |
|
|
|
| 652 |
|
|
|
| 653 |
|
|
----------------------------------------
|
| 654 |
|
|
--
|
| 655 |
|
|
-- ACIA Clock
|
| 656 |
|
|
--
|
| 657 |
|
|
----------------------------------------
|
| 658 |
|
|
my_ACIA_Clock : ACIA_Clock
|
| 659 |
|
|
generic map(
|
| 660 |
|
|
SYS_Clock_Frequency => VGA_Clock_Frequency,
|
| 661 |
|
|
ACIA_Clock_Frequency => ACIA_Clock_Frequency
|
| 662 |
|
|
)
|
| 663 |
|
|
port map(
|
| 664 |
|
|
clk => vdu_clk,
|
| 665 |
|
|
acia_clk => baudclk
|
| 666 |
|
|
);
|
| 667 |
|
|
|
| 668 |
|
|
----------------------------------------------------------------------
|
| 669 |
|
|
--
|
| 670 |
|
|
-- Process to decode memory map
|
| 671 |
|
|
--
|
| 672 |
|
|
----------------------------------------------------------------------
|
| 673 |
|
|
|
| 674 |
|
|
mem_decode : process( cpu_addr, cpu_rw, cpu_vma,
|
| 675 |
|
|
rom_data_out,
|
| 676 |
|
|
user_ram0_dout,
|
| 677 |
|
|
user_ram1_dout,
|
| 678 |
|
|
uart_data_out,
|
| 679 |
|
|
keyboard_data_out,
|
| 680 |
|
|
joystick,
|
| 681 |
|
|
vdu_data_out,
|
| 682 |
|
|
cf_data_out,
|
| 683 |
|
|
cpu_data_out,
|
| 684 |
|
|
secd_state, secd_stopped, secd_ram_dout8, secd_ram_addr_hi )
|
| 685 |
|
|
|
| 686 |
|
|
begin
|
| 687 |
|
|
user_ram0_cs <= '0';
|
| 688 |
|
|
user_ram1_cs <= '0';
|
| 689 |
|
|
rom_cs <= '0';
|
| 690 |
|
|
uart_cs <= '0';
|
| 691 |
|
|
keyboard_cs <= '0';
|
| 692 |
|
|
vdu_cs <= '0';
|
| 693 |
|
|
cf_cs <= '0';
|
| 694 |
|
|
lcd_cs <= '0';
|
| 695 |
|
|
led_cs <= '0';
|
| 696 |
|
|
cpu_data_in <= X"00";
|
| 697 |
|
|
|
| 698 |
|
|
secd_control_cs <= '0';
|
| 699 |
|
|
secd_ram_cs <= '0';
|
| 700 |
|
|
secd_ram_addr_high_cs <= '0';
|
| 701 |
|
|
|
| 702 |
|
|
case cpu_addr(15 downto 14) is
|
| 703 |
|
|
|
| 704 |
|
|
-- Maisforth ROM - $C000 - $FFFF
|
| 705 |
|
|
when "11" =>
|
| 706 |
|
|
cpu_data_in <= rom_data_out;
|
| 707 |
|
|
rom_cs <= cpu_vma; -- read ROM
|
| 708 |
|
|
|
| 709 |
|
|
-- RAM - $0000-$3FFF
|
| 710 |
|
|
when "00" =>
|
| 711 |
|
|
case cpu_addr(13 downto 11) is
|
| 712 |
|
|
when "000" =>
|
| 713 |
|
|
cpu_data_in <= user_ram0_dout;
|
| 714 |
|
|
user_ram0_cs <= cpu_vma;
|
| 715 |
|
|
|
| 716 |
|
|
when "001" =>
|
| 717 |
|
|
cpu_data_in <= user_ram1_dout;
|
| 718 |
|
|
user_ram1_cs <= cpu_vma;
|
| 719 |
|
|
|
| 720 |
|
|
when others =>
|
| 721 |
|
|
cpu_data_in <= (others => '0');
|
| 722 |
|
|
|
| 723 |
|
|
end case;
|
| 724 |
|
|
|
| 725 |
|
|
-- Unmapped - $4000-$7FFF, read as FF
|
| 726 |
|
|
when "01" =>
|
| 727 |
|
|
cpu_data_in <= X"FF";
|
| 728 |
|
|
|
| 729 |
|
|
-- I/O - $8000-$BFFF - Do additional decoding
|
| 730 |
|
|
when "10" =>
|
| 731 |
|
|
case cpu_addr(13 downto 8) is
|
| 732 |
|
|
|
| 733 |
|
|
-- Real I/O $B000 - $B0FF
|
| 734 |
|
|
when "110000" =>
|
| 735 |
|
|
case cpu_addr(7 downto 4) is
|
| 736 |
|
|
|
| 737 |
|
|
-- UART / ACIA $B000
|
| 738 |
|
|
when X"0" =>
|
| 739 |
|
|
cpu_data_in <= uart_data_out;
|
| 740 |
|
|
uart_cs <= cpu_vma;
|
| 741 |
|
|
|
| 742 |
|
|
-- Keyboard port $B010 - $B01F
|
| 743 |
|
|
-- Note in latest System09
|
| 744 |
|
|
-- I have moved the Keyboard
|
| 745 |
|
|
-- to $E020 to make way for the
|
| 746 |
|
|
-- Floppy Disk Controller at $E01X
|
| 747 |
|
|
-- JK. 10th Aug 07
|
| 748 |
|
|
when X"1" =>
|
| 749 |
|
|
cpu_data_in <= keyboard_data_out;
|
| 750 |
|
|
keyboard_cs <= cpu_vma;
|
| 751 |
|
|
|
| 752 |
|
|
-- VDU port $B020 - $B02F
|
| 753 |
|
|
-- Note in latest System09
|
| 754 |
|
|
-- I have moved the VDU to
|
| 755 |
|
|
-- $E030 - JK. 10th Aug 07
|
| 756 |
|
|
when X"2" =>
|
| 757 |
|
|
cpu_data_in <= vdu_data_out;
|
| 758 |
|
|
vdu_cs <= cpu_vma;
|
| 759 |
|
|
|
| 760 |
|
|
-- CF port $B040 - $B05F
|
| 761 |
|
|
-- Note in latest System09
|
| 762 |
|
|
-- I have moved the CF to
|
| 763 |
|
|
-- $E040 - JK. 10th Aug 07
|
| 764 |
|
|
-- However the Trenz TE0141
|
| 765 |
|
|
-- must map the CF on 16 bit
|
| 766 |
|
|
-- word boundaries, so it has
|
| 767 |
|
|
-- to take 2 I/O slots
|
| 768 |
|
|
when X"4" | X"5" =>
|
| 769 |
|
|
cpu_data_in <= secd_ram_dout8;
|
| 770 |
|
|
cf_cs <= cpu_vma;
|
| 771 |
|
|
|
| 772 |
|
|
-- Joystick $B0D0 (read only)
|
| 773 |
|
|
when X"D" =>
|
| 774 |
|
|
if cpu_addr(3 downto 0) = "0000" then
|
| 775 |
|
|
cpu_data_in <= joystick;
|
| 776 |
|
|
end if;
|
| 777 |
|
|
|
| 778 |
|
|
-- LED $B0E0 (write only)
|
| 779 |
|
|
when X"E" =>
|
| 780 |
|
|
if cpu_addr(3 downto 0) = "0000" then
|
| 781 |
|
|
led_cs <= cpu_vma;
|
| 782 |
|
|
cpu_data_in <= led_reg;
|
| 783 |
|
|
end if;
|
| 784 |
|
|
|
| 785 |
|
|
-- LCD Display $B0F0 (write only)
|
| 786 |
|
|
when X"F" =>
|
| 787 |
|
|
if cpu_addr(3 downto 0) = "0000" then
|
| 788 |
|
|
lcd_cs <= cpu_vma;
|
| 789 |
|
|
end if;
|
| 790 |
|
|
|
| 791 |
|
|
when others =>
|
| 792 |
|
|
null;
|
| 793 |
|
|
end case;
|
| 794 |
|
|
|
| 795 |
|
|
-- SECD Control registers - $B100
|
| 796 |
|
|
when "110001" =>
|
| 797 |
|
|
|
| 798 |
|
|
case cpu_addr(7 downto 0) is
|
| 799 |
|
|
|
| 800 |
|
|
-- $B140 -> SECD Status
|
| 801 |
|
|
when X"40" =>
|
| 802 |
|
|
secd_control_cs <= cpu_vma;
|
| 803 |
|
|
cpu_data_in(0) <= secd_stopped;
|
| 804 |
|
|
cpu_data_in(2 downto 1) <= secd_state;
|
| 805 |
|
|
|
| 806 |
|
|
-- $B141 -> SECD Address High
|
| 807 |
|
|
when X"41" =>
|
| 808 |
|
|
secd_ram_addr_high_cs <= cpu_vma;
|
| 809 |
|
|
cpu_data_in <= secd_ram_addr_hi;
|
| 810 |
|
|
|
| 811 |
|
|
when others =>
|
| 812 |
|
|
null;
|
| 813 |
|
|
|
| 814 |
|
|
end case;
|
| 815 |
|
|
|
| 816 |
|
|
-- SECD mapped memory page - $B200
|
| 817 |
|
|
when "110010" =>
|
| 818 |
|
|
cpu_data_in <= secd_ram_dout8;
|
| 819 |
|
|
secd_ram_cs <= cpu_vma;
|
| 820 |
|
|
|
| 821 |
|
|
when others =>
|
| 822 |
|
|
null;
|
| 823 |
|
|
|
| 824 |
|
|
end case;
|
| 825 |
|
|
|
| 826 |
|
|
when others =>
|
| 827 |
|
|
null;
|
| 828 |
|
|
|
| 829 |
|
|
end case;
|
| 830 |
|
|
end process;
|
| 831 |
|
|
|
| 832 |
|
|
--
|
| 833 |
|
|
-- Compact Flash Control
|
| 834 |
|
|
--
|
| 835 |
|
|
compact_flash: process( reset_sw,
|
| 836 |
|
|
cpu_addr, cpu_rw, cpu_vma, cpu_data_out,
|
| 837 |
|
|
cf_cs, cf_rd, cf_wr )
|
| 838 |
|
|
begin
|
| 839 |
|
|
cf_reset <= reset_sw;
|
| 840 |
|
|
cf_cs0 <= not( cf_cs ) or cpu_addr(4);
|
| 841 |
|
|
cf_cs1 <= not( cf_cs and cpu_addr(4));
|
| 842 |
|
|
cf_wr <= cf_cs and (not cpu_rw);
|
| 843 |
|
|
cf_rd <= cf_cs and cpu_rw;
|
| 844 |
|
|
cf_iowr <= not cf_wr;
|
| 845 |
|
|
cf_iord <= not cf_rd;
|
| 846 |
|
|
cf_pwr_en <= '0';
|
| 847 |
|
|
end process;
|
| 848 |
|
|
|
| 849 |
|
|
|
| 850 |
|
|
--
|
| 851 |
|
|
-- Interrupts and other bus control signals
|
| 852 |
|
|
--
|
| 853 |
|
|
interrupts : process( reset_sw, uart_irq, keyboard_irq, reset, joy_up, secd_ram_hold, secd_ram_cs )
|
| 854 |
|
|
begin
|
| 855 |
|
|
cpu_irq <= keyboard_irq;
|
| 856 |
|
|
cpu_nmi <= not joy_up;
|
| 857 |
|
|
cpu_firq <= uart_irq;
|
| 858 |
|
|
cpu_halt <= '0';
|
| 859 |
|
|
cpu_hold <= secd_ram_hold;
|
| 860 |
|
|
end process;
|
| 861 |
|
|
|
| 862 |
|
|
--
|
| 863 |
|
|
-- LCD write register
|
| 864 |
|
|
--
|
| 865 |
|
|
lcd_control : process(lcd_cs, cpu_clk, cpu_data_out)
|
| 866 |
|
|
begin
|
| 867 |
|
|
if falling_edge(cpu_clk) then
|
| 868 |
|
|
if lcd_cs = '1' and cpu_rw = '0' then
|
| 869 |
|
|
lcd_d <= cpu_data_out(3 downto 0);
|
| 870 |
|
|
lcd_e <= cpu_data_out(4);
|
| 871 |
|
|
lcd_rw <= cpu_data_out(5);
|
| 872 |
|
|
lcd_rs <= cpu_data_out(6);
|
| 873 |
|
|
end if;
|
| 874 |
|
|
end if;
|
| 875 |
|
|
end process;
|
| 876 |
|
|
|
| 877 |
|
|
--
|
| 878 |
|
|
-- LED write register
|
| 879 |
|
|
--
|
| 880 |
|
|
led_control : process(led_reg, led_cs, cpu_clk, cpu_data_out)
|
| 881 |
|
|
begin
|
| 882 |
|
|
if reset = '1' then
|
| 883 |
|
|
led_reg <= (others => '1');
|
| 884 |
|
|
elsif falling_edge(cpu_clk) then
|
| 885 |
|
|
if led_cs = '1' and cpu_rw = '0' then
|
| 886 |
|
|
led_reg <= cpu_data_out;
|
| 887 |
|
|
end if;
|
| 888 |
|
|
end if;
|
| 889 |
|
|
|
| 890 |
|
|
end process;
|
| 891 |
|
|
|
| 892 |
|
|
led <= led_reg(3 downto 0);
|
| 893 |
|
|
|
| 894 |
|
|
-- SECD control register
|
| 895 |
|
|
--
|
| 896 |
|
|
secd_control : process(secd_control_cs, cpu_clk, cpu_data_out)
|
| 897 |
|
|
begin
|
| 898 |
|
|
if falling_edge(cpu_clk) then
|
| 899 |
|
|
if secd_control_cs = '1' and cpu_rw = '0' then
|
| 900 |
|
|
secd_stop <= cpu_data_out(0);
|
| 901 |
|
|
secd_button <= cpu_data_out(1);
|
| 902 |
|
|
end if;
|
| 903 |
|
|
end if;
|
| 904 |
|
|
end process;
|
| 905 |
|
|
|
| 906 |
|
|
--
|
| 907 |
|
|
-- SECD RAM Adressing
|
| 908 |
|
|
--
|
| 909 |
|
|
|
| 910 |
|
|
secd_ram_addressing_high : process(cpu_clk, cpu_rw, cpu_data_out, secd_ram_addr_high_cs)
|
| 911 |
|
|
begin
|
| 912 |
|
|
if falling_edge(cpu_clk) then
|
| 913 |
|
|
if cpu_rw = '0' and secd_ram_addr_high_cs = '1' then
|
| 914 |
|
|
secd_ram_addr_hi <= cpu_data_out;
|
| 915 |
|
|
end if;
|
| 916 |
|
|
end if;
|
| 917 |
|
|
end process;
|
| 918 |
|
|
|
| 919 |
|
|
--
|
| 920 |
|
|
-- Joystick register
|
| 921 |
|
|
--
|
| 922 |
|
|
read_joystick : process(cpu_clk, joy_up, joy_right, joy_down, joy_left, joy_fire)
|
| 923 |
|
|
begin
|
| 924 |
|
|
if rising_edge(cpu_clk) then
|
| 925 |
|
|
joystick(0) <= joy_up;
|
| 926 |
|
|
joystick(1) <= joy_right;
|
| 927 |
|
|
joystick(2) <= joy_down;
|
| 928 |
|
|
joystick(3) <= joy_left;
|
| 929 |
|
|
joystick(4) <= joy_fire;
|
| 930 |
|
|
joystick(7 downto 5) <= (others => '0');
|
| 931 |
|
|
end if;
|
| 932 |
|
|
end process;
|
| 933 |
|
|
|
| 934 |
|
|
--
|
| 935 |
|
|
-- LED Flasher
|
| 936 |
|
|
--
|
| 937 |
|
|
my_led_flasher: process(vdu_clk, reset, blink_count)
|
| 938 |
|
|
begin
|
| 939 |
|
|
if reset = '1' then
|
| 940 |
|
|
blink_count <= (others => '0');
|
| 941 |
|
|
elsif rising_edge(vdu_clk) then
|
| 942 |
|
|
blink_count <= blink_count + 1;
|
| 943 |
|
|
end if;
|
| 944 |
|
|
|
| 945 |
|
|
mm_led <= blink_count(25);
|
| 946 |
|
|
|
| 947 |
|
|
end process;
|
| 948 |
|
|
|
| 949 |
|
|
-- Set UART DCD to always true
|
| 950 |
|
|
DCD_n <= '0';
|
| 951 |
|
|
|
| 952 |
|
|
--
|
| 953 |
|
|
-- Feed RGB DAC
|
| 954 |
|
|
--
|
| 955 |
|
|
fpga_r(0) <= red;
|
| 956 |
|
|
fpga_r(1) <= red;
|
| 957 |
|
|
fpga_r(2) <= red;
|
| 958 |
|
|
fpga_g(0) <= green;
|
| 959 |
|
|
fpga_g(1) <= green;
|
| 960 |
|
|
fpga_g(2) <= green;
|
| 961 |
|
|
fpga_b(0) <= blue;
|
| 962 |
|
|
fpga_b(1) <= blue;
|
| 963 |
|
|
fpga_b(2) <= blue;
|
| 964 |
|
|
|
| 965 |
|
|
-- set USB PHY to 16 bit mode so that it generates a 30 Mhz Clock
|
| 966 |
|
|
utmi_databus16_8 <= '1';
|
| 967 |
|
|
|
| 968 |
|
|
-- Hold system in reset until the clock is locked or when the reset
|
| 969 |
|
|
-- key is pressed.
|
| 970 |
|
|
reset <= not reset_sw or not clock_locked;
|
| 971 |
|
|
|
| 972 |
|
|
aud_out <= (others => '0');
|
| 973 |
|
|
|
| 974 |
|
|
ram_bhen <= ram_bhenx;
|
| 975 |
|
|
ram_blen <= ram_blenx;
|
| 976 |
|
|
ram_cen <= ram_cenx;
|
| 977 |
|
|
ram_oen <= ram_oenx;
|
| 978 |
|
|
ram_wen <= ram_wenx;
|
| 979 |
|
|
|
| 980 |
|
|
secd_ram_din32 <= (others => '0');
|
| 981 |
|
|
secd_ram_addr32 <= (others => '0');
|
| 982 |
|
|
secd_ram_read32 <= '0';
|
| 983 |
|
|
secd_ram_write32 <= '0';
|
| 984 |
|
|
|
| 985 |
|
|
end;
|
| 986 |
|
|
|