# Program images Source: [https://docs.qualcomm.com/doc/80-Y8730-5/topic/program_images.html](https://docs.qualcomm.com/doc/80-Y8730-5/topic/program_images.html) Program images include PBL, SBL, and APP images. See the following sections for details about the function, format, and runtime memory status of each program image. ## PBL image Source: [https://docs.qualcomm.com/doc/80-Y8730-5/topic/program_images.html](https://docs.qualcomm.com/doc/80-Y8730-5/topic/program_images.html) The PBL image is in the PBL region of the RRAM, as shown in QCC730 memory and image structure. Qualcomm owns the PBL image and programs it to the PBL region. Customers can't modify it. ### Function The PBL image performs the following tasks: - Handle different boot cases - Choose SBL image from FDT - Authenticate SBL image - Load SBL image ### Image structure Although the PBL image is locked and can't be modified after the chip leaves the factory, a patch for the PBL image is allowed. The patch file is built into the SBL image as an independent segment. ## SBL image Source: [https://docs.qualcomm.com/doc/80-Y8730-5/topic/program_images.html](https://docs.qualcomm.com/doc/80-Y8730-5/topic/program_images.html) The SBL image is stored in the SBL region of the RRAM. For more information, see QCC730 memory and image structure. ### Function The SBL image performs the following tasks: - Choose APP images according to the FDT - Load APP images ### Image structure QCC730 only supports SBL images that are in executable and linking format (ELF). Based on the content, an SBL image mainly includes several segments as shown in the following figure. Figure : SBL image structure PBL patch segment PBL patch segment ELF/PHR ELF/PHR Data segment Data segment Hash segment Hash segment Code segment Code segment - **Hash segment**: This segment includes information for the image signature and hash value of each segment. - **Code/data segment**: These segments include sections of SBL TXT, data, and basic service set (BSS) section. - **PBL patch segment**: This segment includes the patch for PBL. ### Memory layout for SBL SBL runs in the RAM, which has a 64 KB space (`0x80000 to 0x8FFFF`) reserved for SBL. Figure : SBL memory layout sbl_memory_layout Sheet.80 Sheet.2 Separator.4 Separator.18 Separator.19 Separator.20 Sheet.12 PBL patch PBL patch Sheet.13 FDT FDT Sheet.16 PBL PBL Sheet.23 0x20A400 0x20A400 Sheet.24 0x212400 0x212400 Separator.40 Separator.41 Separator.42 Separator.43 Separator.44 Sheet.45 Sheet.46 SBL SBL Sheet.47 32K 32K Sheet.48 ELF ELF Sheet.49 Hash segment Hash segment Sheet.50 Code segment Code segment Sheet.51 Data segment Data segment Sheet.52 PBL patch segment PBL patch segment Sheet.53 Sheet.55 Config table Config table Sheet.56 PBL RAM PBL RAM Separator.9 Separator.10 Separator.11 Sheet.61 RAM RAM Sheet.62 SBL RAM SBL RAM Separator.63 Separator.64 Sheet.65 0xA000 0xA000 Sheet.66 0x80000 0x80000 Sheet.67 0x90000 0x90000 Sheet.68 0xA0000 0xA0000 Separator.71 Separator.72 Separator.73 Separator.76 Dynamic connector Separator.35 Separator.36 ## APP image Source: [https://docs.qualcomm.com/doc/80-Y8730-5/topic/program_images.html](https://docs.qualcomm.com/doc/80-Y8730-5/topic/program_images.html) An APP bin image contains the final programs that run in RRAM, which has 1347 KB space (`0x222400` to `0x372FFF`) for APP. ### Function An APP mainly includes functions such as WLAN, peripheral, and system. ### Image structure Figure : APP image structure app_iamge_structure Sheet.16 Sheet.2 Separator.65 Sheet.4 BDF/REGDB/CALDB segments BDF/REGDB/CALDB segments Sheet.13 RRAM code segment RRAM code segment Separator.14 Sheet.15 RAM data segment RAM data segment An APP bin image includes the following segments according to the content: - **RRAM code segment**: These segments include sections of APP TXT running on RRAM. - **RAM data segment**: These segments include sections of APP data and BSS on RAM. - **BDF/REGDB/CALDB segment**: This segment includes the WLAN BDF, REGDB, and CALDB. ### Memory layout for APP image When an APP image runs, each segment of the image is loaded to the corresponding memory address according to its virtual address. The code and data segments executed in RAM is loaded from flash to RAM, and the code executed in RRAM and REGDB/CALDB are loaded to RRAM. The following diagram illustrates the layout of each memory in detail. Figure : Memory layout for APP app_memory_layout Sheet.105 Sheet.1 RRAM RRAM Sheet.8 Sheet.15 APP APP Sheet.62 RAM RAM Separator.76 Separator.77 Separator.78 Sheet.79 RRAM code segment RRAM code segment Sheet.80 BDF/REGDB/CALDB segment BDF/REGDB/CALDB segment Sheet.108 Sheet.63 Separator.64 Sheet.65 Data segment Data segment Sheet.67 RAM ISR table RAM ISR table Sheet.121 RAM data segment RAM data segment Separator.122 Separator.123 Separator.124 Separator.125 Separator.126 Separator.127 Separator.128 Sheet.129 Kernel segment Kernel segment Sheet.130 Hardware pktmem Hardware pktmem Sheet.131 BSS segment BSS segment Sheet.132 System stack System stack Sheet.133 System heap System heap Sheet.134 Network buffer Network buffer Sheet.135 Unused Unused Last Published: Apr 27, 2026 Previous Topic QCC730 images and binaries Next Topic Configuration BIN binaries