Revision 333
Added by markw over 10 years ago
| common/a8core/address_decoder.vhdl | ||
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ENTITY address_decoder IS
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GENERIC
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(
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low_memory : integer := 0; -- if 0, we assume 8MB SDRAM, if 1, we assume 1MB 'SDRAM'.
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low_memory : integer := 0; -- if 0, we assume 8MB SDRAM, if 1, we assume 1MB 'SDRAM', if 2 we assume 512KB 'SDRAM'.
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stereo : integer := 1;
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system : integer := 0 -- 0=Atari XL, 10=Atari5200 (space left for more systems)
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);
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| ... | ... | |
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end generate;
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gen_low_memory : if low_memory=1 generate
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gen_low_memory1 : if low_memory=1 generate
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-- TODO, check we can use 576k extended RAM ok (PROB NOT)
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-- SRAM memory map (1024k) for Aeon Lite
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SDRAM_CART_ADDR <= "000" & "111" & emu_cart_address(16 downto 0);
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| ... | ... | |
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SDRAM_OS_ROM_ADDR <= "000" & "110" & rom_select(2 downto 0) & "00000000000000";
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end generate;
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gen_low_memory2 : if low_memory=2 generate
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-- TODO, check we can use 320k extended RAM ok (NO)
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-- SRAM memory map (512k) for Papilio duo
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SDRAM_CART_ADDR <= "0000" & "1011" & emu_cart_address(14 downto 0);
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SDRAM_BASIC_ROM_ADDR <= "0000" & "101" & "0000000000000000";
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SDRAM_OS_ROM_ADDR <= "0000" & "101" & rom_select(1 downto 0) &"00000000000000";
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end generate;
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process(
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-- address and writing absolutely points us at a device
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Also available in: Unified diff
Added low memory type 2 - for papilio and its 512k