Short: Replace exec.library's RangerMem check Author: henryk.richter@gmx.net (Henryk Richter) Uploader: henryk richter gmx net (Henryk Richter) Type: util/boot Requires: util/boot/BlizKick or Remus Architecture: m68k-amigaos This blizkick module (usable in Remus, as well) replaces the Ranger Mem detection routine in exec.library by a complete rewrite. The Ranger Mem is also known as A500 Slow RAM or $C0 RAM. Although expansions for this type of RAM are only available to the 16 Bit Amigas (A500/A2000, possibly A1000), this check is present in all exec versions. There were two reasons for me to dig into this. For one, the original routine occasionally mis-detects memory when the kickstart is executed from local FastRAM. In addition, checked memory locations are not restored after testing, potentially destroying reset-proof data (like RAD: or resident kickstart modules). My replacement routine avoids these two issues while still carefully navigating through the memory layout, where the $C0 range mirrors to the custom register range on some computers. Extensive tests have been performed on several Amiga models to date (A500/A600/A2000/A1200/A4000). The replacement routine is even shorter than the original. I've placed the code into public domain but would still appreciate attribution, if my routine is re-used in any project. The replacement was tested with the following exec versions, so far: - 34.5 (1.3) - 40.10 (3.1) - 45.20 (3.9BB2) - 45.23 (3.X) Rostock, 03-Aug-2017, Henryk Richter Usage instructions in Remus (brief) - set up the list of modules to be included in kickstart (as usual) - place the rangermem module into the list of modules, somewhere after "exec" - if the rangermem module doesn't report a failure on "compile", then the patch was successfully applied History 0.3 - changed register usage to make it work with Kick1.3 better 0.2 - fixed a typo in the definitions, previously broke A2000 support 0.1 - first test