TI 99/4A PHP1850C External Floppy Drive

The Texas Instruments Disk Memory Drive is a high-speed, high-volume memory device. The disk drive reads information from and writes information on a 5-1/4 inch diskette (not included). It can read or write information from any place on the diskette, and can rapidly locate any position or file on the diskette. The disk drive spins the diskette at a constant speed and controls the movement of the magnetic head.

To function properly, a disk drive must have a disk controller. The Disk Drive Controller tells the disk drive where to position the magnetic head in order to read or write information properly. The controller also puts a catalog on the disk, making the data that has been written easy to locate. The controller does these things in response to commands which you choose with the Disk Manager Solid State Software’ Command Module or in response to the statements in a TI BASIC program .