Help! looking for a HP document.

[sunjar]

Hello, all:

I recently purchased an HP AJ042A (LTO-4 1840)tape drive with reasonable price, it's new HP spare but it's out of warranty, and now it has a self-test error,  the TAPE and DRIVE LED are keep flashing at the same time. I  need an HP document, the name is:

"Hardware Integration Guide, volume 1 of the HP LTO Ultrium Technical Reference Manual"

There are 5 volumes of this series document. I have found the other 4 volumes, but I cannot find the first volume anyway, including searching in hp.com and hpe.com and google.com. I spent few hours searching for it but nothing founded. Can someone help me find this document? It is very useful to me. I will be very grateful.

The other volume I was found in oracle.com, follow url is one of them (Vol5)

https://docs.oracle.com/cd/E21429_01/en/CRCM2527/CRCM2527.pdf

Thank you very much.

[sunjar]

I still haven't found the first volume of documents, but after referring to a HP documentation of LTO-5 and another documention of HP Ultrium SCSI 2, I have used an RS-422 adapter and a multimeter to find the 5 wires of RS-422 in the ACI terminal at the rear panel . Now I use one The serial debugging tool can already send commands to this tape drive and get some returns, but the returned messages seem abnormal.

I referred to the ACI command in "HP LTO Ultrium tape drives technical reference manual volume 3"  and tried to send "0x12 01  80 00 FF 00" to the tape drive at a baud rate of 9600 to query its serial number, but only returned a few bytes of HEX value, I I also tried some other commands, and I only got a few bytes of return value. I'm not very familiar with ACI commands, have I missed anything?

I used another USB-TTL adapter to connect to a 4P diagnostic port under the front panel of the tape drive and also accessed it with a baud rate of 9600. I got the correct plain text information, such as the prompt "DRIVE RESET", I guess some plain text debugging commands should be entered here, but I don't know any commands and I can't find any relevant information. Can someone provide me with some information? thank you very much.

[Curtis_Ballard]

If the problem is as you describe with the Drive Error LED and the Tape Error LED flashing simultaneously, then the drive is indicating a power on self test (POST) error and those are rarely recoverable.  Power cycles occasionally will recover.  A firmware update might be possible.  The other common 2 LED flashing patterns are usually due to a faulty memory chip in the tape cartridge and is usually cleared when a different tape is loaded.

Those error patterns should be documented in the User's Guide but I didn't go look.

While this drive is an automation drive it is usually possible to connect the drive to a host outside of a library without any special hardware or tools other than a compatible power supply and a fan.  Standalone drives won't work in a library but library drives can run in standalone mode (some qualifiers with specific library drive variants).

Regarding the RS422 interface, the drive may be in ADI mode rather than ACI mode.  ADI is a much more complex protocol that is defined by INCITS/T10 and it uses SCSI commands/responses.  ADI is documented in the INCITS/T10 ADT specification.  ADT-2 is the most common revision supported.  While it is an interesting project to communicate with a tape drive via the RS422 interface, I can't think of an operation you could perform that would clear a POST error using that interface.

[sunjar]

Hi Curtis:

Thank you for providing such useful information. At first I was doubt whether this LTO4 drive can be used independently, but as more and more information is searched and read, especially after reading your replyI have been relieved after seeing this paragraph you said.

Regarding the problem of two LEDs flashing simultaneously, I refer to the user guide. Yes like you said It is indeed a hardware POST failure. But I'm not sure which part is broken. Although my AJ042A has this LED failure, but it can realize some functions, for example, I can use the 'mt' command to control its tape drive eject cartridge or rewind tape in Linux, , but read and write operations will fail. When I use the HP LTT tool under WINDOWS, I can also diagnose the tape drive and get some information about the error. Unfortunately, this information does not specify which part has that error.

This is why I tried to connect the tape drive with RS422 and ACI commands. I want to locate the fault part first, and then try to disassemble it for some testing or repair. This is personal interest. Even if I can't fix it, I have learned some knowledge about LTO drive and have fun. In another HP's Technical Reference Manua on LTO5, I saw that the RS422 interface supports both ADI and ACI, and ACI is the default mode, but currently I have not successfully used the ACI command.

I have repurchased an industrial-grade RS422 interface. I will continue to study ACI commands and continue to look for the manual mentioned in my first post. My RS422 interface information part is obtained from the manuals of LTO5 and SCSI2. , maybe they are different with LTO4.  And I also hope to get the information about the 4P diagnostic port on the front panel. It can now receive the plain text information normally. I just lack the relevant manual or command set.

Thanks again for your reply and these very useful information.