Revision 146
Added by markw about 11 years ago
| common/a8core/address_decoder.vhdl | ||
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gen_low_memory : if low_memory=1 generate
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-- SRAM memory map (512k)
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-- base 64k RAM - banks 0-3 "000 0000 1111 1111 1111 1111" (TOP)
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-- to 512k RAM - banks 4-31 "000 0111 1111 1111 1111 1111" (TOP)
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-- SDRAM memory map (8MB)
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-- base 64k RAM - banks 0-3 "000 0000 1111 1111 1111 1111" (TOP)
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-- to 512k RAM - banks 4-31 "000 0111 1111 1111 1111 1111" (TOP)
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-- to 576k RAM - banks 32-35
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-- CARTS - "101 YYYY YYY0 0000 0000 0000" (BOT) - 2MB! 8kb banks
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-- SRAM memory map (1024k) for Aeon Lite
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SDRAM_CART_ADDR <= "000" & "111" & cart_select(3 downto 0) & "0000000000000";
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SDRAM_BASIC_ROM_ADDR <= "000" & "110" & "00000000000000000";
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SDRAM_OS_ROM_ADDR <= "000" & "110" & rom_select(2 downto 0) & "00000000000000";
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-- TODO, Dmitriy set these correctly!
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SDRAM_CART_ADDR <= "101"&cart_select& "0000000000000";
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-- BASIC/OS ROM - "111 XXXX XX00 0000 0000 0000" (BOT) (BASIC IN SLOT 0!), 2nd to last 512K
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SDRAM_BASIC_ROM_ADDR <= "111"&"000000" &"00000000000000";
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SDRAM_OS_ROM_ADDR <= "111"&rom_select &"00000000000000";
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-- SYSTEM - "111 1000 0000 0000 0000 0000" (BOT) - LAST 512K
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end generate;
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process(
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Also available in: Unified diff
Merged aeon lite 1MB memory support