What is SPL? Difference between SPL and non-SPL

Source: Internet
Author: User
Tags spl android bootloader
What is SPL? Difference between SPL and non-SPL

SPL and second program loader are actually Android bootloader used to guide the system (similar to pc bios .)
In addition to loading the Android system, it also has other functions, including recovery mode, fastboot (fl system), and hboot (???).
In the end, SPL is used to read and write Flash ROM. In addition, SPL checks whether the data file to be flushed is correct.
Currently, most SPL allow us to fl the complete system ROM, but cannot fl the recovery ROM and boot image, because SPL checks the signatures of recovery and boot IMG. However, haykuro modified the SPL and removed the check function, which is engineering SPL,
SPL is so important that you should be careful when refreshing SPL. SPL cannot be restored because SPL has no dedicated devices or technologies.

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As mentioned in the Forum, SPL and non-SPL are not clear. In fact, the SPL is a modified SPL.
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Original article:

So what is an SPL anyway? What does it do?

The SPL, or second program loader, is essential to the android bootloader. it's job is more than just loading the Android OS-it also offers several other boot options, including recovery mode, fastboot, and hboot modes, and ultimately it's the SPL that allows manipulation of the flash NAND on your device. part of the SPL's job is to ensure that the data flashed to the device is correct. most of the current shipping spls (apart from the "perfect SPL's) Let us flash a complete ROM image, but don't let us flash a recovery Rom or boot image as it checks the verification signature. haykuro has modified the SPL's available to remove this check and this is what the engineering SPL's available offer. as the SPL is so crucial to the handset though, you have to be very careful when flashing it as if it's updated incorrectly then you may be incapable of restoring it without specialised hardware and knodge DGE. you essentially have a very expensive brick
From: http://wiki.xda-developers.com/I... tc_sapphire_hacking
Xda-developers.com is a well-known HTC mobile phone Forum abroad, good English, can find good things in this forum and his Wiki,

Here is original SPL list: (from: http://forum.xda-developers.com/showthread.php? T = 529019)
Please update us on any new SPL's so we can include them in this list.

-HBOOT-1.33.0004 (sapp10000): Sapphire PVT 32B ship S-ON G: CPLD-10 (voldafone NL + UK + Australia)
-HBOOT-1.33.0008 (sapp10000 ): sapphire PVT 32a ship S-ON H: CPLD-12 (TIM (Italian)
-HBOOT-1.3300.0009 (sapp10000): Sapphire PVT 32a ship S-ON H: CPLD-12 (Nordic magic a6161)
-HBOOT-1.33.0009 (sapp10000): Sapphire PVT 32a ship S-OFF H: CPLD-12 (Belgian HTC)
-HBOOT-1.33.0009 (sapp10000): Sapphire PVT 32a ship S-ON h: CPLD-12 (Greek)
-HBOOT-1.33.0009 (sapp50000): Sapphire PVT 32a ship S-OFF H: CPLD-11 (Rogers)
-HBOOT-1.33.0009 (sapp50000): Sapphire PVT 32a ship S-ON h: CPLD-12 (Rogers)
-HBOOT-1.33.0010 (sapp10000): Sapphire PVT 32a ship S-ON H: CPLD-12
-HBOOT-1.33.3004 (sapp30000): Sapphire PVT 32B Dev S-ON G: CPLD-10 (ion)
-HBOOT-1.33.3005 from the Japanese ion

Haykuro quote: "T-Mobile mytouch: 1.33.0006 and 1.33.0010 is the dreaded" perfected "SPL ".
This means that it's currently not possible to run "fastboot Boot Image" on these SPL's, so don't try to flash them.
= (1.33.0006 and 1.33.0010 are not cracked yet, so you cannot brush fastboot boot image ")

SPL info
-The g or h at the end identify if it's a Google or HTC SPL
-Eng: Engineering version
-Ship: shipment version
-Dev: Development version (ion)
-S-off and S-on: Security ON and OFF (writing directly to NAND or not), most probably not SPL linked.
-PVT 32a (HTC branded): 288 mb ram/Qualcomm msm7200a ==( motherboard type)
-PVT 32B (Google branded): 192 mb ram/Qualcomm msm7201a
-Cpld xx: What does this mean?

Bytes -------------------------------------------------------------------------------------------------------------------
SPL is responsible for loading the OS Operating System to ram. In addition, SPL also includes many system commands, such as the commands used in mtty. If the SPL is damaged, you can use the recorder to rewrite it. SPL generally provides these functions: Detection of mobile phone hardware, search for system boot partitions, and start the operating system to provide an operation interface for basic system maintenance. You can use data lines and operation terminals (such as PCs) establish a connection, and accept and execute corresponding commands. It contains many commands, such as r2sd, L, doctest (Dangerous command, which erases gsmdata. We often say that the three-color screen is driven by SPL. Check the SD card. When you insert some specially crafted SD cards, the SPL can verify the card at startup and fl it based on the SD card content or execute some commands. This is a bit similar to the start of a PC drive.

Because G1 has a small amount of storage space and cannot meet the daily usage requirements of some users, the storage space of G1 will be increased by refreshing the SPL file. Therefore, the SPL version has 15 MB more storage space than the non-SPL version. However, there is almost no difference between the two in daily use.

White points .,. SPL is like the BIOS of a computer. If it is not SPL, the original BIOS is used, and SPL is a self-made BIOS .. the only difference is that SPL is larger than non-SPL system memory ..

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