README.txt (1351B)
1 2 This is Z80 assembly source for the ZX81 ROM. 3 4 This version came from this URL -- I cannot find the author or more context: 5 https://cdn.hackaday.io/files/289631239152992/ZX81_dual_2018-02-09.htm 6 7 This repository tracks the original as I tidied it up to build under z80asm 8 and will track any further cleanup I do. 9 10 11 It appears to be derived from this version (dated 13-DEC-2004): 12 13 https://www.tablix.org/~avian/spectrum/rom/ 14 https://www.tablix.org/~avian/spectrum/rom/zx81.htm 15 16 "These files were originally hosted at www.wearmouth.demon.co.uk and 17 maintained by Geoff Wearmouth. Unfortunately that website went off-line 18 sometime around the end of 2015 and as of 2017 no copies were available 19 for the casual reader. To keep this valuable historical resource available, 20 some files from that website have been preserved here. Files hosted on 21 this website are from a snapshot captured on 1 September 2015. They were 22 not modified, except for this index page, which was copy-edited for 23 readability." 24 25 The original files are archived in the mirror/ subdirectory for reference. 26 27 28 The hackaday hosted version folds together the original and "shoulders of 29 giants" (enhanced) rom sources with conditional build directives, but more 30 importantly uses descriptive labels like LIST-TOP instead of address-based 31 labels like L0433 which the original rom listing does. 32