128K RAMdisk emulation

128K Spectrum BASIC includes a number of commands for saving files to the extra memory as a RAMdisk. ResiDOS includes emulation of these RAMdisk commands, which work in both 128K and 48K modes.

Setting up the emulated RAMdisk

ResiDOS always uses user area 15 of drive M: to hold RAMdisk files (it uses the hard disk or compactflash card rather than memory, and so can store a lot more files than the 62K or so that the 128K Spectrum can manage). In order to use the RAMdisk commands, therefore, you must first map drive M: to a suitable partition. Here's one suggested way to ensure you always have a 500K RAMdisk available whenever you start the Speccy:

Alternatively, if you want to share a partition that you already use (this is quite safe, as the RAMdisk always uses user area 15, whereas the normal default user area is 0), remap it to drive M: as follows. If this is the drive you want to use by default for normal file operations (on user area 0, for example), you can also do that as shown.

If you are map drive M: to a partition on a FAT disk (using the optional FATfs package), then you should be slightly more careful. Since FAT filesystems don't support user areas, using the RAMdisk will affect all files in the current directory of the drive; there is no user area protection, as with IDEDOS partitions. So be careful if you decide to do something drastic like ERASE !"*.*".

Using the emulated RAMdisk

Once it has been set up, you can use all the standard 128K BASIC commands that access the RAMdisk. The only limitations are that you cannot currently load or save DATA files, or perform MERGE operations, as these facilities are not yet available in ResiDOS.

Some example commands are:

Back to the ResiDOS home page