Category: hardware

RAM CARDS

384KB AST Six Pak

In the early days of the PC, memory was installed on cards to be placed into expansion  slots. This is due to the relatively limited capacity of the system board. The S100 platform offered many more slots than the IBM PC or PC-AT could offer. improved density made it more practical to have fewer slots. …

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RODIME RO352

RODIME RO352

The Rodime RO352 is he first hard disk available in the 3½” format. This disk cost $1,895 when new in 1983. 11MB ST506 interface 306 cylinders 4 heads 17 sectors 306 landing zone type 02 3600rpm The Rodime RO0352  is a ST506 MFM hard disk in the 3½” format . There are two models in the series, RO351 …

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HARD DISK ERRORS

mfm hard disk

Occasionally hard disks run out of spare sectors. Often those errors arise after a few years of use. It is best to format the disk and then check the media to be sure all of the bad sectors are mapped. This way Windows can continue to use the disk for general use. FORMAT Generally format …

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HERCULES GRAPHICS CARD

Hercules_MDA

The Hercules graphics card was released late in 1982. The card is compatible with the IBM MDA card but it offers an additional LPT port saving on a slot and the expense of a printer card. The Hercules card sold for $499 which was typical for a video card in 1982. The card immediately was …

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OUR VIDEO CARDS

IBM MDA

The original PC offered 2 different video cards. The monochrome display adapter (MDA) and the color display adapter (CGA). Soon after that came the enhanced graphics adapter (EGA) and then the video graphics adapter (VGA) became the design standard that sill is in widespread use today. While we have divested of numerous graphics cards, we are …

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HARD DISK CAPACITY

Vendors use a decimal system on top of a binary one. They do this to make their products look bigger. Most disks present data using the binary system, sectors are 512 bytes however modern high capacity disks are now using 4096 byte sectors driven in part by the master boot record limitations and also to …

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HARD DISK LIMITS

102672976p-03-07

One of the most frustrating problems a lot of DIY enthusiasts came up against was BIOS problems that prevented the use of larger capacity disks. In the early days, DOS version 1 which came on a floppy with our original PC could not even use directories. All saved files had to be saved in the …

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BIOS BEEP CODES

1981-ibm-pc5150_a

The IBM PC 5150 and more recent personal computers all use a BIOS beep code to report certain error states. The short beep is followed by loading the operating system from floppy disk or hard disk. 1 short beep is normal 2 short beeps, POST code is shown on screen no beep, power problem or …

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IBM 5150 PERSONAL COMPUTER

1981-ibm-pc5150_a

The IBM PC was released on August 12, 1981.  The machine is model 5150 and the monochrome monitor is model 5151. The desktop design is rather common in the CRT era as monitors were generally placed on top the machine. We bought one of the IBM PC machines in 2001 as the machine was much …

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EPSON MX-80 DOT MATRIX PRINTER

The MX printers were the original line of printers introduced by Epson. The 11″ MX-80 and the larger sized MX-100 with a 15″ carriage suitable for wider print forms. The majority of users purchased the MX-80 which could use fanfold 8½” by 11″ paper. IBM chose the Epson MX-80 to accompany its introduction of the IBM …

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INTEL 8088

intel-8088

The Intel 8088 processor is derived from the 8086 processor using a simpler external 8-bit data bus. Like the 8086, the 8088 has 20 address lines making it able to address up to 1MB. The prefetch is slightly shorter 4 bytes and the prefect is slightly different to accommodate the 8-bit variant. The 6MHz 8088 …

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ATARI 2600

The Atari 2600 was released on September 11, 1977 by Atari. The 2600 is a second generation game console that typically came with a pair of joysticks and maybe a game pad depending on the year purchased. Aftermarket joysticks and pads were available. Unlike first generation machines that were generally hard coded logic, The machine launched …

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INTEL 8048

intel-8048

The Intel 8048 is a CPU designed for embedded afflictions.  Over time, Intel has designed newer versions for other applications. The Intel 8048 was first introduced in the fall of 1976. The successive 8049 is plug compatible with the 8048 offering twice the data and memory. The CPU comes with 1KB of ROM space and 64 …

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ZILOG Z80 CPU

The Zilog Z80 microprocessor was released circa March 1976. The CPU replaces the earlier Intel 8008 processor, The Z80 was a renegade processor when some engineers left Intel to form their own company. The Z80 is a clone of the Intel C8080A with some extensions. Zilog added some more registers and they also made the CPU much …

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FLOPPY DISKS

Floppy disks

The original DA400 provided only 80.6K when formatted with 128 byte sectors and 89.6K when formatted with 256 byte sectors. The Tandon floppy disk on the PC used 256 byte sectors and it held 160K on each side of the diskette. The PC diskette is termed double density as it is double the capacity of …

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