Category : System Diagnostics for your computer
Archive   : SPC_52.ZIP
Filename : SPC.HST

Output of file : SPC.HST contained in archive : SPC_52.ZIP
History of changes in SPC

SPC 5.2 (Mar 20, 1991) adds line 1 support for printer status,
including detection of the PRINT multiplexer.

SPC 5.0 (Jan 16, 1991) is a major change in SPC, focussing on the
need to reduce the overall size of the archive in order to
increase distribution. SPC 4.6's executable was 60k in size. The
new SPC is only 20K in size. This improvement makes SPC the
smallest of all sophisticated multidrive equipment utilities.

The size change was achieved largely by replacing floating point
with fixed point math, by removing the scrollable convertible
direct video, by replacing the bulky error checking used
previously with a more efficient method, and by removal of the
print window (which was of marginal interest anyway). The
elimination of floating point necessitated the introduction of a
LOG simulator to handle the problem of graphing CPU speeds; but it
also involved removal of the code for finding the speed of a

The capabilities of SPC 4.6 which have been taken out are now in a
related program called SPCC.EXE, but will not be available to any
but registered users when SPC returns to distribution as

SPC 5.0 is also superior to SPC 4.6 in several respects:
Identification string input by means of the '=' commandline marker
is now case sensitive, so that the user may display an
identification string in mixed case. Video adaptor detection now
covers more kinds of adaptors. The range of the CPU speed index
is now increased from 1-300 to 1-579, making it possible to graph
the power of the 80586 when available. In addition, without
changing the scaling of SPC's main speed index, the speed test
logic was changed to increase its stability still further, while
reducing the sampling time from 0.82 seconds to 0.71 seconds.
This improvement, together with the removal of the coprocessor
speed test, results in a drastic reduction in SPC's execution
time, notwithstanding that direct video is no longer used. SPC is
now roughly three times faster than the Norton SI. Error handling
in SPC 5.0 is also different from the previous version: While it
still covers all processing without halting processing except for
string space or memory errors, error messages are returned with
section heading descriptions rather than line numbers, and
critical error handling for drives is simplified.

The size of SPC documentation is also drastically cut back, again
to facilitate distribution in much smaller archives.

SPC 4.6 (Sept 6, 1990) is a minor update, the main point of which
is to fix a UART detection bug which prevented the identification
of 16450's. The maximum length of an identification string is now
increased to 31 characters, eliminating the GAME port readout,
which was not reliable for all machine types.

SPC 4.5 (August 23, 1990) adds the Modem Response flag for
detecting the presence of a modem on the given port. Adds
detection of UART to communications section. BIOS data shortened
to accommodate the new info on Line 2. Also added 4.77 MHz 80186
benchmark to speed graph. Adds separate boot drive identification
under DOS 4, so that BOOT may be distinguished from COMSPEC.
CDROM flag is replaced by UNDEF, and the C option is replaced by
the E option (Exclude UNDEF from totals). When SPC encounters a
drive which returns FFFFh total clusters, it simply reports the
drive statistics as read by DOS rather than a CDROM assumption,
while marking the drive UNDEF. Fixes certain minor problems
connected with Novell network operation.

SPC 4.3 (July 14, 1990) fixes a problem encountered while running
SPC 4.2 in DOS 4.0 environments in which SHARE is active on a PS/2
Model 70. Runs done under such conditions apparently generate
permission denied errors at the point where the NUL device was
opened for random access, even though shared mode was specified.
Experiments have shown that this problem is not due to DOS 4.0 and
SHARE, but appears to be associated with TSRs which may be loaded
when SPC is run, or associated with the peculiarities of the Model
70 itself. SPC 4.3 eliminates the use of the NUL device entirely,
resulting in a smaller executable and somewhat faster operation.

Responding to a problem with Email exchanges, the =Identification
commandline option has been added to allow users to put their own
names, or other multi-part identifying phrase, on the display
output, as a convenient way to employ each redirected display as
an identified report. The equals sign tells SPC that everything
following it is to be interpreted as an identification string (up
to but not including a redirect or pipe symbol). A maximum of 24
characters is available. Line 1 of the main display has been
changed to accommodate the identification string.

SPC 4.2 (July 2, 1990) is the first Compuserve release version of
this series, representing a giant step beyond SPC 4.0. This
version introduces very fast speed indices for both processor and
coprocessor, as well as full keyboard information and readouts on
the communications port DTR, RTS, and Carrier Detect lines. It
also adds sensitivity to Hercules monitors, Verify and Share
status detectors, as well as identification of the type of
underlying network in which SPC is run. Most important, however,
is that this version solves the old problem of identifying SUBSTed
drives by using direct DOS services calls. In addition, SPC 4.2
adds detection of the LASTDRIVE, summary status support for the
printer and DOS spooler, and DOS colour preservation support for
direct video operation.

Previous versions of SPC go back to early 1988 but are not
described here.

  3 Responses to “Category : System Diagnostics for your computer
Archive   : SPC_52.ZIP
Filename : SPC.HST

  1. Very nice! Thank you for this wonderful archive. I wonder why I found it only now. Long live the BBS file archives!

  2. This is so awesome! 😀 I’d be cool if you could download an entire archive of this at once, though.

  3. But one thing that puzzles me is the “mtswslnkmcjklsdlsbdmMICROSOFT” string. There is an article about it here. It is definitely worth a read: