This is a modified version of MEGA65 Open ROMs (https://github.com/MEGA65/open-roms), forked at upstream commit ad178dbe4d48cd6a317737a8e0e7e662f7e33d32. Modified by Christian Werner, 2026-10-14 and 2026-10-15, for the mc64 computers of arnitech, a set of Minecraft mods (https://git.susdog.de/chris/arnitech). The fork lives at https://git.susdog.de/chris/open-roms, branch mc64. Changes: - src/,,config_mc64.s: a new build configuration, copied from src/,,config_c64.s, with its own config ID ($6D), the brand "MC64", and BCD_SAFE_INTERRUPTS turned off. - Makefile: targets for that configuration, build/kernal_mc64.rom and build/basic_mc64.rom, made the same way as the c64 ones. - src/kernal/iec/ciout.s (2026-10-15): CIOUT buffers its byte in TBTCNT, where the send routine takes it from, not in BSOUR (upstream PR #113). - src/kernal/iec/close_iec.s (2026-10-15): CLOSE sends LISTEN, $E0 plus the secondary address, and UNLISTEN; it sent a command ORed with zero page $E0 and no LISTEN. - src/kernal/iec/chkin_iec.s, ckout_iec.s (2026-10-15): CHKIN and CHKOUT take the secondary address from SAT, not from LAT, the logical file numbers. - src/kernal/iec/tksa.s (2026-10-15): TKSA sends the secondary address it is given, without ORing $90 into it (upstream issue #116). - src/kernal/iec/iec_tx_byte.s (2026-10-15): a data byte that no listener holds DATA for sets ST to $80 (device not present) and returns, instead of waiting forever. - NOTICE: this file. The licence terms are unchanged; see LICENSE, COPYING, and COPYING.LESSER.