| Command ID | Name | Function | | :--- | :--- | :--- | | 0x01 | HELLO | Ping device, get version string (usually "1.0") | | 0x04 | SECTOR_SIZE | Set the logical block size (usually 512 or 4096) | | 0x05 | PROGRAM | Write a chunk of data to a specific LBA | | 0x06 | READ | Read a chunk of data from a specific LBA | | 0x07 | ERASE | Erase a sector (SEND, not SECURE) | | 0x20 | RESET | Force reboot the device out of EDL |
But be warned: With V1.0, there is no safety net. A PROGRAM command sent to the wrong LBA (like mmcblk0p1 ) will destroy the PBL region instantly. No confirmation. No undo. Qfl Qualcomm Flash Loader V1.0
When a Qualcomm device is in Emergency Download (EDL) mode (9008), the ROM boot ROM (PBL) is waiting for a signed loader over UART or USB. The V1.0 designation refers to the specific handshake command structure and the initial patch level of the Secondary Boot Loader (SBL) negotiation. | Command ID | Name | Function |
Think of it as the BIOS handshake of the mobile world. V1.0 is the most primitive and, ironically, the most universal. Later versions (V2.0, V3.0) introduced rolling code anti-replay protections, but V1.0 operates on a deterministic, static challenge-response. No undo
