Progression of Early Business and Personal Computers

06/08/2013

Early Prominent CPU Hardware Groups/Companies (to name only a few)

Early Software Prominent Companies

• Digital Research
• MicroPro
• T-Maker

CP/M Varieties that vastly contributed to the PC explosion

• The original CP/M that made the initial "Cohesive Force" that allowed many different hardware designed systems to be "Compatable" with each other, in spite of their hardware differences.
• MP/M - The system that worked like the "Big Boys Computer", in that it allowed multi-tasking and multi-user capability from a single 8-bit CPU system, with multiple printer, multi-interface, and networking capabilities. It also had very advanced directory access and filtering methods, some of which are not available in the IBM PC of today.
• CP/Net - The system that allowed disk or diskless systems to "Bootstrap" up into a fully functional networking system.
• Freeware and Shareware enhancements that allowed CP/M to reach to new heights of ability, some of which have not been achieved with todays systems.

I think it rather ironic that the release of that first IBM PC, that so many folks enthusiastically accepted, had these rather interesting major faults:

1. It incorporated a "Crippled CPU", rather than the Intel 8086 (this was strictly a monetary move, to take advantage of existing 8-bit hardware currently available, but todays users still suffer from that blunder).
2. It incorporated a "Crippled Floppy Disk Drives" that were antique by comparison to what was available.
3. It incorporated a "Crippled Floppy Drive Access" that only allowed for 2 drives, rather that industry standard allowance of at least 4 drives (also where someone incorporated that "cute idea" of the cable twist, rather than take advantage of the existing 4-drive selection available on each drive).
4. It incorporated a "Crippled Memory System of only 64Kb" that did not even allow upgrades. Most all of the 8-bit CPU Systems had that and more available, and we were using up to 512Kb memory pages (and more) with those 8-bit systems. The CPU chosen for the first IBM PC would handle 1024 Kb.
5. It incorporated a "Crippled Video System" using a primitive digital monitor system, instead of analog.
6. Apple and a number of other computer systems were using analog display systems, which allowed for a much greater capability in display variance.
7. It incorporated a "Crippled Operating System" (questionably "Cloned" from another existing system), that due to it's structure "borrowed" from another system (CP/M), still haunts us today by its awkwardness in how and where the OS hardware MUST reside, making memory management problems a serious issue. By utilizing what was adequate for a 16-bit address system, into what was to be an obvious growing system, set the stage for problems ahead.
8. It was seriously crippled because it did NOT incorporate any capability for any type of Hard Drive into the system. There were a large number of 8-bit CPU Systems that were using Hard Drives. I was already using an 85Mb Drive in my Z80 CPM System, when the first IBM system was introduced with a 10Mb Drive.
9. The type of DB-25 Connectors used for Serial v.s. Parallel Input/Output were completely reversed from what was most commonly used by industry, where the DB-25F socket was commonly used for RS-232 Serial.