/* Imported from Wayback Machine
   Original URL : https://www.retrobrewcomputers.org/doku.php?id=builderpages:plasmo:frr512k:rev0:emulate_512kram_rom
   Snapshot date: 2023-01-31
   Generator    : wayback-archiver
*/

====== Emulation of RC2014 512K RAM/ROM Board ======

The original [[https://rc2014.co.uk/modules/512k-rom-512k-ram-module/|RC2014 512K RAM/ROM board]] has 32 banks of RAM and 32 banks of ROM; each bank is 16KB in size. This modification of FRR512K emulate RC2014's 512K RAM/ROM board.

[[https://www.retrobrewcomputers.org/lib/exe/fetch.php?tok=be0532&media=https://www.retrobrewcomputers.org/lib/plugins/ckgedit/fckeditor/userfiles/image/builderpages/plasmo/frr512k/rev0/frr512k_r0_comp_for_32x16kbanks.jpg|{{https://www.retrobrewcomputers.org/lib/exe/fetch.php?w=600&h=338&tok=1a48a1&media=https%3A%2F%2Fwww.retrobrewcomputers.org%2Flib%2Fplugins%2Fckgedit%2Ffckeditor%2Fuserfiles%2Fimage%2Fbuilderpages%2Fplasmo%2Ffrr512k%2Frev0%2Ffrr512k_r0_comp_for_32x16kbanks.jpg?600x338|www.retrobrewcomputers.org_lib_plugins_ckgedit_fckeditor_userfiles_image_builderpages_plasmo_frr512k_rev0_frr512k_r0_comp_for_32x16kbanks.jpg}}]]

[[https://www.retrobrewcomputers.org/lib/exe/fetch.php?tok=51b7ad&media=https://www.retrobrewcomputers.org/lib/plugins/ckgedit/fckeditor/userfiles/image/builderpages/plasmo/frr512k/rev0/frr512k_r0_solder_wired_for_32x16kbanks.jpg|{{https://www.retrobrewcomputers.org/lib/exe/fetch.php?w=600&h=386&tok=91b688&media=https%3A%2F%2Fwww.retrobrewcomputers.org%2Flib%2Fplugins%2Fckgedit%2Ffckeditor%2Fuserfiles%2Fimage%2Fbuilderpages%2Fplasmo%2Ffrr512k%2Frev0%2Ffrr512k_r0_solder_wired_for_32x16kbanks.jpg?600x386|www.retrobrewcomputers.org_lib_plugins_ckgedit_fckeditor_userfiles_image_builderpages_plasmo_frr512k_rev0_frr512k_r0_solder_wired_for_32x16kbanks.jpg}}]]

[[https://www.retrobrewcomputers.org/lib/exe/fetch.php?media=builderpages:plasmo:frr512k:rev0:frr512k_rev0_cpld_32x16k_banks.zip|CPLD design]] file

===== Engineering Changes to Rev0 PCB =====

[[https://www.retrobrewcomputers.org/lib/exe/fetch.php?tok=c8d25b&media=https://www.retrobrewcomputers.org/lib/plugins/ckgedit/fckeditor/userfiles/image/builderpages/plasmo/frr512k/rev0/frr512k_r0_comp_mod_for_32x16kbanks.jpg|{{https://www.retrobrewcomputers.org/lib/exe/fetch.php?w=400&h=241&tok=4ed210&media=https%3A%2F%2Fwww.retrobrewcomputers.org%2Flib%2Fplugins%2Fckgedit%2Ffckeditor%2Fuserfiles%2Fimage%2Fbuilderpages%2Fplasmo%2Ffrr512k%2Frev0%2Ffrr512k_r0_comp_mod_for_32x16kbanks.jpg?400x241|www.retrobrewcomputers.org_lib_plugins_ckgedit_fckeditor_userfiles_image_builderpages_plasmo_frr512k_rev0_frr512k_r0_comp_mod_for_32x16kbanks.jpg}}]]

[[https://www.retrobrewcomputers.org/lib/exe/fetch.php?tok=9a7a40&media=https://www.retrobrewcomputers.org/lib/plugins/ckgedit/fckeditor/userfiles/image/builderpages/plasmo/frr512k/rev0/frr512k_r0_solder_mod_for_32x16kbanks.jpg|{{https://www.retrobrewcomputers.org/lib/exe/fetch.php?w=400&h=237&tok=b351af&media=https%3A%2F%2Fwww.retrobrewcomputers.org%2Flib%2Fplugins%2Fckgedit%2Ffckeditor%2Fuserfiles%2Fimage%2Fbuilderpages%2Fplasmo%2Ffrr512k%2Frev0%2Ffrr512k_r0_solder_mod_for_32x16kbanks.jpg?400x237|www.retrobrewcomputers.org_lib_plugins_ckgedit_fckeditor_userfiles_image_builderpages_plasmo_frr512k_rev0_frr512k_r0_solder_mod_for_32x16kbanks.jpg}}]]

=== CUT ===

On the component side of rev0 PCB, cut trace from D7 to CPLD pin 19 near CPLD

On the solder side of rev0 PCB, cut trace from nM1 to CPLD pin 4 near the RC2014 connector

On the solder side of rev0 PCB, cut trace from A14 to RAM & ROM near the RC2014 connector

=== JUMPERS ===

A14 to CPLD, RC2014-pin 2 to CPLD-pin4

Bank0 to A14 of EPROM, CPLD-pin19 to U5-pin29

D4 to CPLD, U5-pin18 to T4

D5 to CPLD, U5-pin19 to T3