User's Guide
Chapter 3 Emulated DLT7000 SCSI Commands
Write Buffer (3Bh)
276 Quantum DX-Series Software Interface Guide
Download 
Microcode Mode 
(100b)
3
Using buffer offsets, the host can download the firmware image into the 
target’s buffer in pieces. These commands do not cause the new image to 
become active. A Download and Save Mode WRITE BUFFER command 
must be issued for the image to become active.
The tape drive must be empty of tape medium to allow downloading of 
an image. This is a safeguard against accidentally starting a firmware 
update. If a tape cartridge is loaded when all or part of a firmware image 
has been downloaded, another WRITE BUFFER with Download 
Microcode mode will be rejected. The firmware image must be 
downloaded in integral multiples of 8K bytes.
Any error on a WRITE BUFFER command causes any downloaded image 
data to be discarded and the download must be restarted from the 
beginning.
Caution: During the actual reprogramming of the FLASH 
EEPROM, if any type of power-fail occurs, or if the 
reprogramming fails before completion, the tape drive 
subsystem becomes unusable and the tape drive must be 
replaced.
Download 
Microcode and 
Save Mode (101b)
3
This mode is used to download and save the entire image at once, or to 
download the image and save it, or to cause a save operation after the 
image data has been downloaded using the Download Microcode mode 
(without the Save). This mode of the WRITE BUFFER command causes 
the image data to be verified and the Flash EEPROM firmware area to be 
updated. Also, when it is updating the EEPROM, it disconnects from the 
SCSI bus and will not respond until the update is complete. 
When the Save operation is successfully completed, the firmware restarts 
itself, causing the Power On Self Test (POST) to be run, and two UNIT 
ATTENTION conditions are generated: POWER UP RESET and 
OPERATING CODE HAS CHANGED.










