Files
super6502/hw/fpga/addr_decode.sv
Byron Lathi 51c348bc7c Increase sd card addr width by 1
Adds a new memory location for data accesses.
2022-04-11 13:57:07 -05:00

25 lines
753 B
Systemverilog

module addr_decode(
input logic [23:0] addr,
output logic sdram_cs,
output logic rom_cs,
output logic hex_cs,
output logic uart_cs,
output logic irq_cs,
output logic board_io_cs,
output logic mm_cs1,
output logic mm_cs2,
output logic sd_cs
);
assign rom_cs = addr >= 24'h008000 && addr < 24'h010000;
assign sdram_cs = addr < 24'h007fe0 || addr >= 24'h010000;
assign mm_cs1 = addr >= 24'h007fe0 && addr < 24'h007ff0;
assign hex_cs = addr >= 24'h007ff0 && addr < 24'h007ff4;
assign uart_cs = addr >= 24'h007ff4 && addr < 24'h007ff6;
assign board_io_cs = addr == 24'h007ff6;
assign mm_cs2 = addr == 24'h007ff7;
assign sd_cs = addr >= 24'h007ff8 && addr < 24'h007ffe;
assign irq_cs = addr == 24'h007fff;
endmodule