Category: hardware

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 …

Continue reading

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 …

Continue reading

SEAGATE ST-225

st-225

The Seagate ST-225 is a 20 MB hard disk. ST-412 20MB Data rate 5 Mbit/sec Seek time 85ms Platter capacity 10.5 MB AT drive type 2 Heads 4 Spin rate 3600 RPM Actuator Stepper Interface MFM Form factor 5¼” half-height This disk has not performed well with RLL controllers. We suggest MFM controllers which is …

Continue reading

COMMODORE 64

Commodore-64

The Commodore 64 was announced at the CES in 1982. The MSRP was $595. MOS 6510 CPU 64KB RAM 20KB ROM 2 joystick ports cassette tape support ROM cartridge support Commodore was making some 400,000 units a month over the first 5 years before sales softened due to the rising low cost PC and changing …

Continue reading

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 …

Continue reading

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 …

Continue reading

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 …

Continue reading

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 …

Continue reading

SEAGATE ST-412

102672976p-03-07

The Seagate ST-412 is a 10 MB hard disk. ST-412 10MB Data rate 5 Mbit/sec Seek time 85ms Platter capacity 5 MB AT drive type 1 Heads 4 Spin rate 3600 RPM Actuator Stepper Interface MFM Form factor 5¼” full-height

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

Continue reading