List of copy protected software titles on cassette

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Uses of the 'Locked' bit of the Acorn cassette format aside, this page lists titles that either cannot be copied using *LOAD and *SAVE (given sufficient memory) or that depend on highly accurate hardware-level behaviour. It is intended as a compatibility checklist for emulator developers.

8N1, 8N2, 8O1 etc. refer to asynchronous frame protocols -- the number of data, parity and stop bits to each byte. O and E respectively refer to odd and even parity, as understood by major UARTs.

Copy protected software titles on cassette
Title Publisher Author Platform Description VLSI SERPROC compatible
3D Grand Prix Software Invasion Mick O'Neill & Dave Mendes BBC B Block numbers of GP5 and GP6 increase in steps of 255. Yes
Alien 8 Ultimate Play The Game Kevin Edwards(?) BBC B Custom loader + evil VIA decoding Yes
Android Attack Computer Concepts Paul Hiscock BBC B Filename A1 has random numbers of spaces added in each block. The file is saved in ordinary looking Acorn blocks, alternating between 8N1 and 8E1. Inter-block gaps are in the pattern of sequential recordings, but in place of carrier breaks are 'security cycles' comprising audible lengths of low tone. They may be significant to the copy protection, or just artefacts of a 'repeater' copying a stop-start recorded master tape. Yes
Arkanoid Imagine Peter Johnson & Jason Sobell (copy protection) BBC B The name of the largest file changes at every block. Its block numbers start from &0100. Yes
BASICODE 2 The Chip Shop (BBC Radio 4) ir. P.G.M. Maathuis BBC A/B Not copy protection per se, but the programs themselves were transmitted in a continuous 8N2 stream. The 1984 Chip Shop issue of the loader and saver programs, with a few small changes, will work with the Serial Processor.[1] Yes*
BoulderDash Tynesoft Andrew Bennett[2][3] BBC B VIA timer based decryption.[4]  ?
Caveman Capers Icon Jason Sobell et al. BBC B Loader checks for two streams totalling 53 standard bytes before the final file. No
Citadel Superior Michael Jakobsen & Lars Østerballe BBC B Filename changes upper & lower case Yes
Doctor Who and the Mines of Terror Micropower Gary Partis BBC B The game was supplied as a cassette and accompanying paged ROM. The cassette "has bytes alone with bits of pilot tone before the next byte." Clusters of low and high tone also appear. There are "some non-standard format blocks as well."[5]  ?
Eagle's Wing Software Invasion Boris Obinskofh BBC B The name of the largest file contains a control character that changes at every block. Yes
Elite Acornsoft Braben & Bell BBC B Non-standard blocks, interrupt routines and obfuscated code.[6] Yes
Estra Firebird A.J.Field BBC B Loads a custom stream that swings between 8E1 and 8O1. Yes
Facemaker Applied Systems Knowledge (ASK) Gloria Callaway BBC B Loader checks for a stream of 11 standard bytes at two points. No
Fortress Pace Microsystems Mat Newman BBC B Final part is a data stream that switches from 8N2 to standard format (8N1) and back to 8N2. No
Hareraiser Prelude Haresoft  ? BBC B "To scupper the pirates, the tapes include information that the average computer owner will not be able to reproduce. Should copies be taken, the user will not be aware that all the data is not present. As a secondary precaution, each tape has its own registration card which the purchaser must complete."[7] "The cassettes are specially coded so there is no possibility of duplication and each one must correspond to a special code from the originator."[8] Given the circumstances surrounding Haresoft however, the claims are questionable. Kleen found no protected data in Hareraiser Prelude.  ?
Hyper Sports Imagine  ? BBC B VIA timer based decryption.[4]  ?
Impact! Audiogenic Gary Partis BBC B Saves frame set files made up of custom 8O1 blocks. Program is only locked. Yes
Impossible Mission U.S.Gold Peter Johnson & Kevin Edwards (copy protection) BBC B VIA timer based decryption. Yes
Knight Lore Ultimate Play The Game Kevin Edwards[9] BBC B Custom loader + evil VIA decoding Yes
Lunar Jetman Ultimate Play The Game  ?  ? "bewilderingly complicated protection"[10]  ?
Manic Miner Software Projects D.J.Coathupe BBC B In most files the block number starts from &FF00. Yes
Nightshade Ultimate Play The Game Kevin Edwards BBC B Non-standard stream; Multiple-stage decryption using VIA timers after loading. Subject of a huge thread on STH on making 6502 and VIA emulation good enough to decrypt it. Yes
Orbit Zero Graphic Research  ? BBC B "uses non-standard data blocks" [11]  ?
Poker Ducksoft Tom Pinone BBC B Does VDU 23 commands when LISTed to screw up the display, halt DRAM refresh and erase memory. Yes
Revs Acornsoft Geoff Crammond BBC B Loads a continuous 25 KB standard stream, displayed as though loading a file named 'Revs02'. Yes
Skirmish Go-Dax Software Delos D Harriman BBC B Custom loader with display synchronised to tape. Loads a 25 KB stream that switches from 8O1 to 8N1. Yes
Stairway To Hell Software Invasion  ? BBC B Names of some files change in length at every block. Zeroed load and exec addresses after first block. Block numbers increase by 255 each time.[12] Yes
Starquake Bubble Bus Kenton Price, Stephen Crow & Gary Partis (copy protection) BBC B Uses an encrypted custom loader that takes control of the hardware and reads in 101-byte blocks of 8O1 data. [13] Yes
Superman: The Man Of Steel Tynesoft  ? BBC/Electron "no one can crack the customised tape loader"[14]  ?

References

  1. In file bc/load line 1590, LDX #3 must be changed to LDX #8 to select the 19200 baud receive rate, as found in OS 1.20.
  2. Stairway to Hell Forums post by Peter Wood, 10th September 2007.
  3. Andrew Bennett, "BoulderDash for BBC Electron".
  4. 4.0 4.1 BBC Micro Mailing List post by Bill Carr, 28th April 2003.
  5. Stairway to Hell Forums post by Fraser Ross, 1st February 2004.
  6. Reply to Rich Talbot-Watkins by John Kortink, 28th April 2003.
  7. The Micro User, August 1984, p.24
  8. A & B Computing, October 1984, p.13
  9. Excerpt from A&B Computing, February 1988. Argus Press.
  10. Stairway To Hell Forums post by Rich Talbot-Watkins, 6 October 2010
  11. Stairway To Hell Forums post by Arcadian, 10 August 2009
  12. BBC Micro Mailing List post by Shaileen Shah, 31st July 2000.
  13. Reply to Bill Carr by Rich Talbot-Watkins, 28th April 2003.
  14. The DVD, Dave Edwards, Acorn Electron World.

-- beardo 16:43, 7 October 2010 (UTC)