The Qualcomm Firehose Programmer is a specialized tool used to flash firmware onto Qualcomm chipsets found in various devices, including smartphones, tablets. It operates in Emergency Download (EDL) mode, a low-level software interface that allows direct access to the device's hardware.
Flashing firmware updates
Performing backups and restorations
Modifying system partitions
Supports various firmware formats, including .mbn, .elf, .bin and .melf for new devices
Offers command-line interface for advanced users
Provides some GUI-based tools for easier flashing
Requires specific hardware cables and drivers for connection
Unless things have radically changed between ZF8 and ZF 10, specific cables should not be required most of the time. I bought one and couldn't even use it.
If you can access your phone in adb, you can reboot-bootloader, and proceed. If you cannot access adb, start your phone in recovery by holding vol up + power.
When at the bootloader, there is a special fastboot command to instantly enter edl mode, no cable, no shorting or removing battery required: "fastboot oem enter-dload" will put your device into EDL mode. Then it's a matter of making sure you have the right Qualcomm drivers installed on your computer in order to communicate with it. I recommend downloading the latest QPST because QPST had everything needed in one package. AFAIK You can get the firehose files from any RAW/Full (not OTA update -- ones that are not only payload.bin).