OPL and Solid State Disks



*** Types of Solid State Disk

Solid State Disks (SSDs) are explained in detail in the User 
guide. There are two main reasons for using them:

*) To provide more room for storing information.

*) To make backup copies of important information, in case 
you accidentally change or delete it (or even lose your Series 3a).

There are two types  Ram SSDs and Flash SSDs. 
They fit into the SSD drives marked "A" and "B", 
at either side of the Series 3a.

*) Flash SSDs are for storing or backing up information which 
is infrequently changed. This includes finished OPL programs.

*) Ram SSDs are for storing or backing up information which 
changes frequently. This includes OPL programs you are still writing 
or testing.

You can, though, save programs and data files to either kind of SSD, 
as you see fit.

*** How to put programs on an SSD

To create a new OPL module on an SSD, use the `New file' option in 
the System screen as before, but set the "Disk" line of the dialog 
to "A" or "B" as required.

To copy an OPL module onto an SSD, move onto the module name where 
it is listed under the Program icon, and use the `Copy file' option 
on the `File' menu. Set the `To file: Disk' line to "A" or "B". 
If you want this copy to have a different name to the original, type 
the name to use, on the `To file: Name' line. The new copy will appear 
in the list under the Program icon, but with "[A]" or "[B]" 
after its name. 

To copy the translated version of an OPL module, move onto the 
name in the list under the RunOpl icon (to the right of the Program 
icon), then proceed as before. 

*** SSDs from inside OPL

Your OPL programs can create or use data files on SSDs. To do so, 
begin the name of the data file with "A:" or "B:"  
for example:

CREATE "B:JKQ",A,X1$,X2$

tries to create a data file "JKQ" on an SSD in "B", while 

DELETE "A:X300"

tries to delete a data file "X300" on an SSD in "A".

Don't confuse the drive names "A" and "B" with the logical 
names "A", "B", "C" and "D". Logical names are unaffected 
by which drive a data file is on.

The internal memory can be referred to as "M:", if required. For 
example:

PROC delx300:
  LOCAL a$(3),c%
  a$="MAB" :c%=1 REM default to "Internal"
  dINIT "Delete X300 data file"
  dCHOICE c%,"Disk:","Internal,A,B"
  IF DIALOG REM returns 0 if cancelled
    DELETE MID$(A$,c%,1)+":X300"
  ENDIF
ENDP

In this example, "MID$(A$,c%,1)" gives ""M"", ""A"" or 
""B"", according to the choice made in the dialog. This is added 
on the front of "":X300"" to give the name of the file to delete  
""M:X300"", ""A:X300"" or ""B:X300"".

When using data files with SSDs, follow the same guidelines as with 
OPL programs  Flash SSDs are for one-off or "finished" information, 
while Ram SSDs are for information which is still being changed.

*** Directories and DOS structure

The internal memory and SSDs use a DOS-compatible directory structure, 
the same as that used by disks on business PCs. For more details, 
see the `Advanced Topics' chapter.