Disassembly of the iriver H300 original firmware
General
I took the time to start a serious disassembly of the H300 1.30eu iriver firmware to see if I could find out some things about the power management, and the handling of the remote controls.
Progress
I have so far disassemled the boot process up to when the actual firmware code is copied to RAM and started.
Findings so far
Nothing spectacular, but here are a few things that they do and we should:
PCF50606
Some general purpose outputs are set like this when enabling the backlight:
| Register |
Value |
Meaning |
Comment |
| 0x39 |
0x07 |
GPO0ACT? = 1, GPO1ACT? = 0 |
I don't yet know what these pins do |
| 0x3a |
0x3b |
GPOOD0ACT? = inv. PWM, GPOOD0STB? = PWM HiZ |
The backlight pin is tristated when the device is off |
Also, when they turn off the device, they set GPOOD2 and GPOOD3 like this:
| Register |
Value |
Meaning |
Comment |
| 0x3b |
0x00 |
GPOOD2ACT? = HiZ, GPOOD2STB? = HiZ |
UDA1380 Reset |
| 0x3c |
0x07 |
GPOOD3ACT? = 0, GPOOD3STB? = HiZ |
I don't know what this pin does |
For some reason, the application retains the OPMOD settings for the regulators:
IOREGC = (IOREGC & 0xe0) | 0x14;
D1REGC = (D1REGC & 0xe0) | 0x1f;
D2REGC = ((D2REGC & 0xe0) | 0x18) & 0x1f; /* What a silly thing to do... */
D3REGC = (D3REGC & 0xe0) | 0x10;
LPREGC = (LPREGC & 0xe0) | 0x0f;
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