R-IDSC-E/R Experiments

I purchased this R-IDSC-E/R SCSI to IDE converter as part of some IDE to CF experiments. The goal was to use CF in older SCSI systems.

R-IDSC-E/R background

The R-IDSC-E/R is a SCSI to PATA IDE converter board, claimed to be a successor to the IDSC21-E, both made by I-O Data. I-O Data does not reference these devices, however the wayback machine finds this. The jumper setting document is mirrored locally here At the bottom of this page are the features and specifications as listed by the seller.

Configuring the R-IDSC-E/R

There is a block of 9 jumpers on the R-IDSC-E/R for configuring it. The jumper setting PDF for the IDSC21-E lists 10 jumpers, but jumper position 0 has been omitted on my board. Jumper 1 on my board is indicated by a small triangle next to the jumper block. Jumper 1 is on the "top" of the board on the same edge as the 50 pin SCSI connector. To get started, start with the basics. Set the SCSI ID jumpers (1-3) appropriately, and set the SCSI termination as desired (jumper 9). When connecting a hard disk, set jumper 5. Additionally, if your hard disk supports UDMA (most do), set jumper 7. You should be good to go at this point.


The original goal was to use an IDE-CF adapter with this device in order to to use CF as the hard disk for SCSI systems. Since most CF cards to not support UDMA, jumper 7 should be left off so the converter will use PIO mode. I've also found setting it to SCSI-1 with jumpers 4 and 5 set, 6 unset, works well for the macs I've tried it in.
However, I have had problems with the Mac formatting software, even third party, initializing the drive. I've had good luck with Lido.


Listed features & specs


The R-IDSC-E is the next generation model (same compatibility) of the IDSC21-E. This model is provided as RoHS compliant 5 of 6 on materials, manufacturing, and preparations: 
1) Cadmium and Cadmium compounds 
2) Mercury and Mercury compounds 
3) Hexavalent chromium compounds 
4) Polybrominated biphenyls (PBB) 
5) Polybrominated biphenyl ethers (PBDE) 
This model manufacturing uses Pb solder process. Not 100% for RoHS.
Ultra SCSI (Dual Edge) 
20MB/S, 10MB/S, 5MB/S (Synchronization) transmitting, Asynchronous transmitting.
Custom design for 5 inch ATAPI Device
For IDE bus Ultra DMA/66 
Transmitting mode PIO 0-4, DMA 0-2, UDMA 0-4
512 byte FIFO 
If installed with two 256 byte FIFO, transmission will be smooth without overhead between IDE to SCSI.
40MHz High speed CPU
SCSI-3 standard
Disconnecting and reconnecting functions available.
SCSI data bus parity.
SCSI CCS (Common Command Set)

Model Type: IDE-SCSI Converter for 5 inch ATAPI Device
Host Interface: Ultra SCSI (for Dual Edge)
Hard Disk Interface: ATAPI-6, PIO-4, DMA0-2, UDMA0-4
Max Data Transmission Speed: 40MB/S (Dual Edge Mode)
Interface Connector: 50 Pin SCSI Connector
Number of Drives: 1 Unit
Voltage: DC5V +/-5%
Current: 400mA
Environment Temperature: 5 - 55?C
Environment Humidity: 20 - 80% (without dew condensation)
Size: 126.3 x 34.8 x 22.5mm
Weight: 35g


Blake Petterson pointed me at the following links to manuals for the iodata r-idsc-e and the idsc21 models:

Updated: June 14 2013