Siemens EWSD Drives

Solid State Disks Ltd

Dependable Data Storage Solutions

The Elektronisches WählSystem Digital (EWSD), translated to Electronic Digital Switching System in English, is a widely installed German telephone exchange system, originally introduced in 1975 by Siemens AG, but discontinued in 2017.

We offer high reliability solid-state replacement drives for a wide variety of telecoms equipment.

Our CF2SCSI™ SCSIFlash™ drives can be used to replace drives with either internal storage media, such as magnetic HDDs and SSDs, or which use removable media, such as magnetic tapes, optical disks (CD / DVD), floppies and solid-state memory cards.

For example, Compact Flash Drive Replacement for Siemens EWSD SSNC

Supporting integration with FastFile PC (collecting Billing Data). Connection via SCSI bus and via V24 with EWSD (as OMT).

The following EWSD systems have been tested and approved by a European Repair entity and (amongst others) can be replaced.

Module # S30807-U2594-X300 (HECI EQMYAE0DAA)
Hard Disk Drive (HDD) (S30122-U789-X-2 (ST-39173N))
Module # S30807-U2593-X200 (HECI EGM8JF0BRA)
Magneto-Optical (MO) Drive (S30122-U563-X400)
IOPUNI: S30810-Q1257-X-A2IOPUNI: S30810-Q1257-X-A2M:MDD S32007-U107-X100-4M:IOPUNI S30810-X1-S1 (SW)
IOPUNI-2: S30813-Q336-X-2IOPUNI-2: S30813-Q336-X-2M:MOD S32006-Q1028-X-A7M:IOPUNI S30810-X-14 (HW)
M:IOPUNI S30810-X1-16 (SW)M:IOPUNI S30810-X1-16 (SW)M:MPUC S30813-Q82-X400-4 (HW)M:IOPUNI S30810-X1-16 (SW)
M:IOPUNI S30810-X-14 (HW)IOPUNI S30810-X-14 (HW)M:MPUC S30813-Q82-X401-8 (SW)M:IOPUNI S30810-X-14 (HW)
M:IOPUNI S30810-X1-S1 (SW)M:IOPUNI S30810-X1-S1 (SW)PSTN EWSD V15 with SSNC and CP 113C.
MDD board: S30807-U2593-X200-2 MDD board: S30807-U2593-X200-2MOD: S30807-U2593-X200-2
MOD board: S30807-U2593-X200-2 M: IOPUNI S30810-Q1257-X1-13Test completed successfully on both sides CP and MP successfully.
M: IOPUNI S30810-Q1257-X1-19Test completed successfully on COPYGEN (CP) and COPYGENMP to SSD MO successfully.
M: IOPUNI2 S30813-Q336-X1-9Test completed successfully with Transfile to and from CP SSD MO
M:IOPUNI S30810-Q1257-“X1”-“15/06 “ CP113 APS V9Test completed successfully with ETH connection/ filetransfer from SSD MO to PC with Flash2GUI
MOD board: S30807-U2617-X-6
MDD board: S30708-U2635-X-1
The SCSIFlash drives have Successfully tested on both C, D, & E and V17 of APS.
MDD board: S30807-U2618-X-6"MPUD:S30813-Q208-X800-4 "MOD
MDD board: S30708-U2635-X-1EWSD S12, S14 (HiS700, SON8) In DEVELOPMENT STATUS
IOPUNI-2: S30813-Q336-X-2
MPUD:S30813-Q208-X800-4 "
MOD/MP board S32006-Q1028-X-A5/01

Where to next?

What is SCSIFlash™?

Our drive solves the growing and increasingly expensive problem of repairing or replacing ageing and failing SCSI-based 2.5-inch, 3.5-inch and 5.25-inch hard disk drives, magneto optical drives, quarter-inch tape drives and floppy disk drives on computer-based legacy equipment used in telecoms and other industries.

Combining proven SCSI drive architectures with industry-standard, solid-state Flash-based memory technology, our drives are drop-in replacement for any style of SCSI-based drive.

We have two families of products:

  • SCSIFlash™. The storage media used is Compact Flash (CF), up to 128GB capacity, and the SCSI interface (SASI, SCSI-1 and SCSI-2 architectures) is standard (narrow) 8-bit with data transfer rates of up to 10MB/s.
  • SCSIFlash-Fast™. The storage media used is either CFast or M.2 SSD, up to 1TB capacity, and the data transfer rate is up to 80MB/s. SASI, SCSI-1, SCSI-2 and Ultra3 are supported, and the interface is automatically detected as being standard/narrow (8-bit SCSI, wide (16-bit) SCSI, single-ended (SE) or low voltage different (LVD) signalling.

Our drives are completely programmable, enabling the SCSI driver implementation nuances of the original equipment to be fully emulated. This means you won’t have to make any changes to your system. Our drives are truly swap-in replacements.

For further information on SCSIFlash and SCSIFlash-Fast, and to access data sheets, please visit here:

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