Encoder firmware - v3l0c1r4pt0r/lkv-wiki GitHub Wiki

Encoder has a firmware file usually with extension .bin. It contains raw dump of ROM memory, which is then loaded at address 0.

Image structure

     0 -   1000: IRQ0 - IRQ15
 7d100 -  b53bf: code section
 b53c0 -  bd5bf: data section
 bd5c0 -  d8d6f: another code section
 d8d70 - 10205f: another data section
200000 - 283104: SMEDIA02 container

Code base

Code starting at address 0x7d100 consists of FreeRTOS port with bunch of custom modules. It uses FreeRTOS for scheduling of the tasks. Task names are:

task_main
PALFILE
MPS
AUDIO_IN
VIDEO_ENCODER
STREAM_MUX
STORAGE
HDMI_LoopThrough
USBEX
KEY_MANAGER

Source files

Following source files are known to be present in firmware:

tasks.c - partially common with FreeRTOS codebase
timers.c - partially common with FreeRTOS codebase
msgq.c
thread.c
heap.c

Encoder CPU-part responsibilities

upgrade SMEDIA02 (copy to different memory area)
audio driver
I2S initialization
FAT32 filesystem support (purpose unknown)
other/unknown

ISA

Machine code present in *.bin firmware blob is for OpenRISC 1000 (or1k) core.

SPI Flash

Most likely this is later stored on U4 chip.