The original IBM PC (IBM 5150) (as seen in Terry Stewart's computer collection)
HTML-код
- Опубликовано: 30 окт 2023
- Terry Stewart (tezza) talks about vintage/classic computers in his collection: The original IBM PC (IBM 5150). A further description can be seen here: www.classic-computers.org.nz/.... This video replaces an earlier copy which had very poor audio. See the View Numbers and Comments before the refresh at www.classic-computers.org.nz/...
Наука
Not many people know, but the PC could use both a color and monochrome screen at the same time (different info on each) because the color and monochrome cards used different port addresses and memory regions. You only needed software to control them both.
Borland later used this to allow one screen to be a debugger (usually the monochrome screen) when programming. It worked really well. I used a dual screen setup with Turbo Pascal on a clone 8088 system.
Also the PC speaker could create tones without the CPU having to toggle the speaker. Once you set the frequency it would continue until you stopped it. Unlike the Apple II and ZX Spectrum where the CPU could only toggle the speaker.
It also had hardware timers that could generate an interrupt. The Apple II and ZX Spectrum had no hardware timers. Not sure about the TRS-80 Model I or the PET but I don't think they did.
Bill Gates gets a lot of flack about saying that 640K should be enough for anybody. But you have to remember that at the time CP/M machines only had 64K, so 640K was ten times the RAM of the current machines. Also the first PC floppies were only 320K so 640K of RAM would have been able to hold 2 full disks worth of information.
I think IBM would have come out ahead if they would have licensed their BIOS to other companies. They probably could have made more money from that than they would have selling computers.
Yes, correct. I think I mention this in my video on the IBM XT.
One of the major advantages IBM had with the 5150 was that it was a kind of secret project. It had its own team far away from the IBM corporate suits where the machine was developed. The team acted very independently from the larger IBM corporate structure. Most of IBM didn't even know the 5150 was under development.
As such, it was developed as an almost entirely open system. The only real proprietary part of the 5150 was the BIOS and even here is was only partially closed. The functions it provided were published openly so software vendors could create software for it..
Had they developed it as a normal IBM project, it would have been a major flop. This is largely what happened to the PC Jr.
Yes, I think the "skunkworks" nature of its development, taking it away from the rigid bureaucracy of their traditional R+D processes, had a lot to do with their success and certainly the speed to market. And that speed was needed, given how fast computer technology was moving at the time.
What a gem! Back in 1987-88, I had the opportunity to work with some of those machines when my high school peers gravitated towards the CGA Amstrad 1512 for its gaming capabilities. I was more interested in programming and comparing the processing speeds between the formidable IBM machines and my ZX Spectrum, along with other Z80-based 8-bit computers. It was slightly disappointing to find that the 8088 at 4.77 MHz was only marginally faster. However, the design of those machines, much like their manuals, is utterly iconic-comparable to an old Ford Mustang or Porsche 911. They are timeless classics that maintain their value. Even today, I can easily imagine myself typing away on one of those machines if I were a creative writer.
While I knew most of this, I enjoyed your presentation of it. 🙂 The IBM PC is about as old as I am, and it boggles my mind to think about how much computers -- especially micros -- have evolved just during my own lifetime, especially as regards the almost complete takeover of home computing by "IBM PC compatibles" in that time.
I've been loving watching these again after so long. What a great collection!
Glad you're enjoying them!
Amazing collection!!
Thanks for watching
Thanks for these videos.
No worries! Glad you are enjoying them.
The reason why the FPU was sold separate was to make some more money for the manufacturer but nowadays you get chips like the A10-7800k and INTEL XEON ©®
None of the CPU mentioned in the videostream don't have the ability to accelerate encryption algorithms and it is only recently that there are instructions like ...
AESDEC
AESDECLAST
AESENC
AESENCLAST
AESIMC
AESKEYGENASSIST
PCLMULQDQ
have become available to speed up encryption and decryption.
CGA actually exceeds the C64's graphics. It doesn't have hardware sprites or scrolling, but it does have 16 colors. Unlike the C64 which has "rules" about the color which greatly limits the color capability of the C64, CGA in some game modes can display 16 colors without limitation. The CGA 160x200 composite video is one such mode. Any pixel on the screen can be any of 16 colors without limitation. A software sprite can be 16 colors. Many early PC games look outstanding next to the games machine's graphics when viewed through composite video. This trick only works with composite video.
For an excellent example, check out a video of Burgertime for PC composite video on youtube . The colors are used to great effect. I think there is also a version of Ms Pac Man which uses the composite video mode.
A C64 can only display 4 color (3 plus no color) sprites whether in hardware or software and there is color sharing across the sprites. IOW, you cannot display 4 different sprites each using 4 different colors..
The C64's 160x200 multi-color mode can only display 2 or 4 colors within any 8x8 pixel square and they have to share some of the colors.
The low resolution screens on both, which are essentially text mode screens, allows all 16 colors on a per cell basis. Meaning a red A can be next to a blue B which can sit next to a green C. But, each character cell can only be made up of 2 colors, the desired color and no color. IOW, the screen color is shared among all cells.
When it comes to sound, the 64 is superior in most ways, but especially sound quality.
cool ibm pc
Thanks!