HOW2 see down into Abs-Mem?

Lets's look at the SD-card: df => /dev/mmcblk0p1 57288 16896 40392 30% /boot dd if=/dev/mmcblk0p1 count=8 | hexdump -C >> SDcard ==

00000000 eb 3c 90 6d 6b 64 6f 73 66 73 00 00 02 10 10 00 |. /home/pi/stikMBR == 00000000 33 c0 8e d0 bc 00 7c fb 50 07 50 1f fc be 1b 7c | 3.....|.P.P....|| ... 000001f0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 55 aa |..............U.|

OK, so perhaps "eb 3c 90" is not X86 code. But ARMcodeS are 4 bytes?

Let's see if this `ALO` can decode the MBR-bytes? => *.Tool System.Directory ^ => ARM.Decoders.Tool =FAIL ? previous version of ALO showed some decoding/dis-assembly capability? Look in older dirs. => refers *Decoder.Mod ==> ALO.ARMDecoder.Mod exports: Decode

Try:--------------------------- => ARMDecoder.Decode ARMDecoder.Obj = MindBlowing TextFrame: ARMDecoder.Dec Object file dump

Name: ARMDecoder Tag: 245 48 Key: 496F14AC

Code size: 16536 Var size: 101732 Strconst size: 1232 Entries: 1 Pointers: 8 TDescs: 0 Imports: 12

Imports: 496F14A5 Files 496F14A5 OFS 496F14A6 Texts 496F14A6 Objects ... skip Zillion lines of info ... Procedure Decode: 00002740 E92D5000 STMDB SP!, {FP LR } 00002744 E1A0C00D MOV FP,SP 00002748 E3A0B000 MOV RB,0H 0000274C E3A0A0AC MOV RA,ACH 00002750 E52DB004 STR RB,[SP,-4H]! 00002754 E25AA001 SUB S RA,RA,1H ... skip Zillion lines of info ...

? Does this look like ARMcode ? If so, then I want to look down into Abs-memory. ============================

PS. this capability for rPi is available from

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It probably doesn't need to use the X86 standard MBR. But it does need to use an MS-DOS partition table. Any executable code in the MBR is ignored, other than to identify the fact that it is an MBR with partition table.

As you have been told before the first partition on the SD card needs to be in MS-DOS format (FAT-xx) for the GPU boot ROM to use it. It is the only format supported by the Broadcom chip.

It has nothing to do with CPU type. The ARM isn't even running at this stage.

Just to go over the boot stage again:

1) GPU BOOT ROM looks at storage for MS-DOS partition as first partition. 2) GPU Loads 1st stage bootload "bootcode.bin". This is in GPU code. 3) bootcode.bin loads second stage bootloader. "start.elf". This is also GPU code. 4) Start.elf reads config.txt and loads Kernel and cmdline.txt into ARM memory. 5) Start.elf starts up the ARM core. 6) Linux (or other OS) boots.
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Dom

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