ProDOS #8
Dealing with /RAM

Revised by Matt Deatherage (November 1988)
Written by Kerry Laidlaw (October 1984)

This Technical Note formerly described conventions for dealing with the built-in ProDOS 8 RAM disk, /RAM.

Section 5.2.2 of the ProDOS 8 Technical Reference Manual now documents the conventions on how to handle /RAM, including how to disconnect it, how to reconnect it, and precautions you should follow if doing either, which were covered in this Note. The manual also includes sample source code.

Executing the sample code which comes with the manual to disconnect /RAM has the undesired effect of decreasing the maximum number of volumes on-line when used with versions of ProDOSĘ8 prior to 1.2. This side effect is because earlier versions of ProDOS 8 do not have the capability to remove the volume control block (VCB) entry which is allocated for /RAM when it is installed.

In later versions of ProDOS 8 (1.2 and later), this problem no longer exists, and you should issue an ON_LINE call to a device after disconnecting it. This call returns error $28 (no device connected), but it also erases the VCB entry for the disconnected device.

Further Reference

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