Re: Compliance test configuration
Just a thought. Doubling the data lines from 32 to 64 doesn't necessarily mean that they are being clocked any faster. I would assume they increase the word size, put it on the buss lines in parallel fashion and then clock that data down the line at the same time, and at the same buss rate as before. It might be more appropriate to consider these as additional I/O lines and follow those guidelines - adding until less than a 2 dB increase. Considering that these are data lines and not clock signals it seems unlikely that the data patterns would match such that you would get coherent addition of the signals unless you synchronize the data patterns which has, in my opinion little or nothing to do with typical or real operation of the equipment. If its easy to get the system with the 64 bit bus, you're way ahead to do that because there is no question about it, and you address all of the variables. If not document it in your test along with the rational but be prepared to defend it if necessary, to then find a unit to test, and then worry about field retrofit that test failed. Engineering risk management. Note, I didn't say management risk management I'm fairly certain I know that answer. Gary - Original Message - From: Rachid Sehb mailto:rs...@rheintech.com To: 'ravinder.ajm...@hgst.com' ; Rachid Sehb mailto:rs...@rheintech.com Cc: emc-p...@majordomo.ieee.org Sent: Wednesday, September 03, 2003 5:56 PM Subject: RE: Compliance test configuration Ajmani, Yes that is correct, having the unit transmitting information at the highest data rate is the goal. Rachid Sehb EMC engineer mailto:rs...@rheintech.com mailto:rs...@rheintech.com The information contained in this electronic mail message is privileged and confidential, and is intended only for use of the addressee. If you are not the intended recipient, you are hereby notified that any disclosure, reproduction, distribution or other use of this communication is strictly prohibited. If you have received this communication in error, please notify the sender by reply transmission and delete the message without copying or disclosing it. From: ravinder.ajm...@hgst.com [mailto:ravinder.ajm...@hgst.com] Sent: Wednesday, September 03, 2003 8:51 PM To: Rachid Sehb Cc: emc-p...@majordomo.ieee.org Subject: RE: Compliance test configuration Hello Rachid, Thank you very much for your reply. In this case, the EUT is the disk drive, which is connected to SCSI Adapter through the SCSI interface. The 64-bit interface is strictly between the PC and the SCSI Adapter, and does not affect the transfer rate between Adapter and the disk drive. The only benefit of using 64-bit interface is to sustain the data rate when connected to a large number of disk drives. I would assume that as long as I am transferring data between Adapter and the disk drive at the maximum transfer rate, the type of interface between Adapter and PC (both of which are already agency approved) should not matter. Regards, Ravinder Server PCB and Flex Development Hitachi Global Storage Technologies Email: ravinder.ajm...@hgst.com Rachid Sehb rs...@rheintech.com 09/03/2003 05:34 PM To:'ravinder.ajm...@hgst.com' ravinder.ajm...@hgst.com cc: From:Rachid Sehb rs...@rheintech.com Subject:RE: Compliance test configuration Hello Ajmani, In most cases the standard would like the worst case to be tested, so my advice would be to test the 64 bits. Rachid Sehb EMC engineer mailto:rs...@rheintech.com mailto:rs...@rheintech.com Rhein Tech Laboratories, Inc. http://www.rheintech.com/ http://www.rheintech.com Electro Magnetic Engineering and Testing, Wireless Testing, Electrical Safety Testing, PCB and Hardware Design Engineering 360 Herndon Parkway, Suite 1400, Herndon, VA 20170 Tel: 703-689-0368 x127 ; Fax: 703-689-2056 The information contained in this electronic mail message is privileged and confidential, and is intended only for use of the addressee. If you are not the intended recipient, you are hereby notified that any disclosure, reproduction, distribution or other use of this communication is strictly prohibited. If you have received this communication in error, please notify the sender by reply transmission and delete the message without copying or disclosing it. From: ravinder.ajm...@hgst.com [mailto:ravinder.ajm...@hgst.com] Sent: Wednesday, September 03, 2003 3:08 PM To: 'emc-p...@majordomo.ieee.org' Subject: Compliance test configuration Hi EMC Experts, I want to test a U320 SCSI disk drive for agency compliance. All the U320 SCSI Host Bus Adapters require 64-bit PCI slot, although they will also work in the 32-bit slot. My question is do I have to use a PC with 64-bit PCI bus for my testing (these PCs are hard to come by), or can I use a PC with 32-bit PCI bus. I
RE: Compliance test configuration
Ajmani, Yes that is correct, having the unit transmitting information at the highest data rate is the goal. Rachid Sehb EMC engineer mailto:rs...@rheintech.com mailto:rs...@rheintech.com The information contained in this electronic mail message is privileged and confidential, and is intended only for use of the addressee. If you are not the intended recipient, you are hereby notified that any disclosure, reproduction, distribution or other use of this communication is strictly prohibited. If you have received this communication in error, please notify the sender by reply transmission and delete the message without copying or disclosing it. From: ravinder.ajm...@hgst.com [mailto:ravinder.ajm...@hgst.com] Sent: Wednesday, September 03, 2003 8:51 PM To: Rachid Sehb Cc: emc-p...@majordomo.ieee.org Subject: RE: Compliance test configuration Hello Rachid, Thank you very much for your reply. In this case, the EUT is the disk drive, which is connected to SCSI Adapter through the SCSI interface. The 64-bit interface is strictly between the PC and the SCSI Adapter, and does not affect the transfer rate between Adapter and the disk drive. The only benefit of using 64-bit interface is to sustain the data rate when connected to a large number of disk drives. I would assume that as long as I am transferring data between Adapter and the disk drive at the maximum transfer rate, the type of interface between Adapter and PC (both of which are already agency approved) should not matter. Regards, Ravinder Server PCB and Flex Development Hitachi Global Storage Technologies Email: ravinder.ajm...@hgst.com Rachid Sehb rs...@rheintech.com 09/03/2003 05:34 PM To:'ravinder.ajm...@hgst.com' ravinder.ajm...@hgst.com cc: From:Rachid Sehb rs...@rheintech.com Subject:RE: Compliance test configuration Hello Ajmani, In most cases the standard would like the worst case to be tested, so my advice would be to test the 64 bits. Rachid Sehb EMC engineer mailto:rs...@rheintech.com mailto:rs...@rheintech.com Rhein Tech Laboratories, Inc. http://www.rheintech.com/ http://www.rheintech.com Electro Magnetic Engineering and Testing, Wireless Testing, Electrical Safety Testing, PCB and Hardware Design Engineering 360 Herndon Parkway, Suite 1400, Herndon, VA 20170 Tel: 703-689-0368 x127 ; Fax: 703-689-2056 The information contained in this electronic mail message is privileged and confidential, and is intended only for use of the addressee. If you are not the intended recipient, you are hereby notified that any disclosure, reproduction, distribution or other use of this communication is strictly prohibited. If you have received this communication in error, please notify the sender by reply transmission and delete the message without copying or disclosing it. From: ravinder.ajm...@hgst.com [mailto:ravinder.ajm...@hgst.com] Sent: Wednesday, September 03, 2003 3:08 PM To: 'emc-p...@majordomo.ieee.org' Subject: Compliance test configuration Hi EMC Experts, I want to test a U320 SCSI disk drive for agency compliance. All the U320 SCSI Host Bus Adapters require 64-bit PCI slot, although they will also work in the 32-bit slot. My question is do I have to use a PC with 64-bit PCI bus for my testing (these PCs are hard to come by), or can I use a PC with 32-bit PCI bus. I will appreciate your advice in helping me decide this. Regards, Ravinder Server PCB and Flex Development Hitachi Global Storage Technologies Email: ravinder.ajm...@hgst.com
RE: Compliance test configuration
Hello Rachid, Thank you very much for your reply. In this case, the EUT is the disk drive, which is connected to SCSI Adapter through the SCSI interface. The 64-bit interface is strictly between the PC and the SCSI Adapter, and does not affect the transfer rate between Adapter and the disk drive. The only benefit of using 64-bit interface is to sustain the data rate when connected to a large number of disk drives. I would assume that as long as I am transferring data between Adapter and the disk drive at the maximum transfer rate, the type of interface between Adapter and PC (both of which are already agency approved) should not matter. Regards, Ravinder Server PCB and Flex Development Hitachi Global Storage Technologies Email: ravinder.ajm...@hgst.com Rachid Sehb rs...@rheintech.com 09/03/2003 05:34 PM To:'ravinder.ajm...@hgst.com' ravinder.ajm...@hgst.com cc: From:Rachid Sehb rs...@rheintech.com Subject:RE: Compliance test configuration Hello Ajmani, In most cases the standard would like the worst case to be tested, so my advice would be to test the 64 bits. Rachid Sehb EMC engineer mailto:rs...@rheintech.com mailto:rs...@rheintech.com Rhein Tech Laboratories, Inc. http://www.rheintech.com/ http://www.rheintech.com Electro Magnetic Engineering and Testing, Wireless Testing, Electrical Safety Testing, PCB and Hardware Design Engineering 360 Herndon Parkway, Suite 1400, Herndon, VA 20170 Tel: 703-689-0368 x127 ; Fax: 703-689-2056 The information contained in this electronic mail message is privileged and confidential, and is intended only for use of the addressee. If you are not the intended recipient, you are hereby notified that any disclosure, reproduction, distribution or other use of this communication is strictly prohibited. If you have received this communication in error, please notify the sender by reply transmission and delete the message without copying or disclosing it. From: ravinder.ajm...@hgst.com [mailto:ravinder.ajm...@hgst.com] Sent: Wednesday, September 03, 2003 3:08 PM To: 'emc-p...@majordomo.ieee.org' Subject: Compliance test configuration Hi EMC Experts, I want to test a U320 SCSI disk drive for agency compliance. All the U320 SCSI Host Bus Adapters require 64-bit PCI slot, although they will also work in the 32-bit slot. My question is do I have to use a PC with 64-bit PCI bus for my testing (these PCs are hard to come by), or can I use a PC with 32-bit PCI bus. I will appreciate your advice in helping me decide this. Regards, Ravinder Server PCB and Flex Development Hitachi Global Storage Technologies Email: ravinder.ajm...@hgst.com
