CPU2.ASM - 8086/8088/V20/V30 speed check/benchmark program
- 01/07/86 - Stephen R. Davis, Kim Levitt

-->>> CPU2.ASM is an adaptation by Kim Levitt of an assembly langauge
program that was modified by Stephen Davis, combined with a Sieve of
Eratosthenes benchmark also listed by Stephen R. Davis in his article
"Turbo Charge Your 8086/8088 Computer" that was published in two parts
in the Nov/Dec'85 and Jan/Feb'86 issues of Micro/Systems Journal. *

The speed check/benchmarks will run on any 8086/8088 or V20/V30 based
microcomputer running under MS-DOS. (It may run under CP/M-86 and/or
Turbo-DOS also, but not sure.)

It will display the number of seconds taken to execute a "mixed
instruction set" in a repeat loop, and compute the relative "clock
speed" of your system as compared to the standard 4.77 Mhz of the
standard IBM-PC. The Sieve of Eratosthenes benchmark is included
also as it is a favorite used in benchmark comparisons between
different computers. The number of seconds taken to complete ten
repetitions is displayed. This program can be used to demonstrate
the relative performance of a particular machine or to document the
increase in performance gained by upgrading from a 8086/8088 to a
V20/V30 chip. It does NOT use any of the special 80186/80286/V20/V30
instructions and so will run on a normal 8088 or 8086 just fine.

* (The article is about using a NEC uPD70108 (V20) or uPD70116 (V30)
microprocessor in your 8088/8086 or compatible instead of the
Intel 8088 or 8086 to speed up the relative performance of your
computer without increasing your system's clock speed or adding a
coprocessor or replacement motherboard. I added a V30 to my AT&T
PC 6300 and have anywhere from 25% to 100% faster performance, and
it only cost me about $20! Not only that, but with the V20-80.COM
program (in the public (freeware) domain) you can run CP/M-80 software
on your MS-DOS system!!) I HIGHLY recommend you swap your Intel chip
for the new NEC super chip, ESPECIALLY if you have a 8086 (true 16-bit).

-- Notes/update by Kim Levitt
sysop, MBBS Headquarters PDSE
(213) 653-6398 (300/1200/2400 baud)

SAMPLE RUN (ON AT&T PC 6300 WITH V30 8 MHZ):

C:\>CPU2

CPU2: SPEED CHECKER/BENCHMARK PROGRAM
01/07/86 -- Stephen R. Davis, Kim Levitt

BENCHMARK #1: - Mixed Instruction Repetition

Please wait...

Execution time is 10.00 secs on a 4.77 Mhz 8088
with no waits on RAM access.

Actual execution time here = 03.90 seconds.
Effective 8088 clock speed = 12.23 Mhz

BENCHMARK #2 - Sieve of Eratosthenes, 10 reps

Please wait...

Execution time is 3.68 secs on a 4.77 Mhz 8088
with no waits on RAM access.

Actual execution time here = 01.60 seconds.

C:\>

V20/V30 BENCHMARK COMPARISONS USING NORTON UTILITIES "SYSINFO.COM" (v3.0)
AND "CPU2.COM" BENCHMARK PROGRAMS -- 01/07/86 -- Kim Levitt

IBM PC 8088 4.77 MHZ IBM PC V20 4.77 MHZ

NORTON SYSINFO - 1.00 1.70 (70.0% INCREASE)
CPU2 #1 - 10 - 4.77 9.5 - 5.02 (5.26% INCREASE)
CPU2 #2 - 3.68 3.57 (3.08% INCREASE)

AT&T PC 6300 8086 8 MHZ AT&T PC 6300 V30 8 MHZ

NORTON SYSINFO - 1.90 3.90 (105% INCREASE)
CPU2 #1 - 4.7 - 10.14 3.9 - 12.23 (20.51% INCREASE)
CPU2 #2 - 1.80 1.60 (12.5% INCREASE)

NORTON SYSINFO = "Performance factor relative to IBM-PC"
CPU2 #1 = Mixed Instruction repetition (secs - effective Mhz)
CPU2 #2 = Sieve of Erastosthenes, 10 reps (secs)