EXP-MX250 RadiSys Hard Drive and Floppy Drive Controller Module

The RadiSys EXP-FDM is a single-slot VME floppy disk module. The 3.5" drive is intended for use in a single VMEbus card slot. The 3.5" EXP-FDM is driven by connecting a data cable to the unit by way of a 34 pin header on the product's front panel. The intent is to get data from an adjacent EXM-MX unit. Power for the unit comes through this same 34 pin header. The disk drive itself is cabled to the main board through a 26 pin flex circuit cable. The main board contains no P1 or P2 connector and is shorter than standard VME board products. This is to ensure use in a VME card slot that contains a RadiSys subplane, ie. BP-6 product, which would cause mechanical interference. EPC4, EPC5, EPC8, or EXP-MC will take the EXM-MX card to interface with the EXP-FDM.


The EXP-MS/MX mass storage modules are 6U (VMEbus-size) modules that plug into the EXM expansion interface of a RadiSys VMEbus embedded PC. The EXPMS/MX mass storage module contains a disk controller board, a hard disk, and a 1.44 MB floppy diskette drive. Depending on the capacity and physical size of the internal hard disk, an EXP-MS/MX module occupies either two or three VMEbus slots. Front-panel connectors are provided for adding an external SCSI hard disk and either a 3.5" or a 5.25" external floppy drive. There are also three indicator LEDs. Two indicate that the VMEbus +5V and +12V supplies are available (the +12V supply is needed for the hard disk drive). The third LED is lit whenever a hard disk access is underway.

All EXP-MS/MX models are fully MS-DOS compatible, as is the external SCSI port. The internal hard disk in an EXP-MS40 uses a SCSI interface. The EXP-MX series uses a faster IDE (Integrated Device Electronics) interface.