ROMS and Radios

[Guest jayw08]

This has probably been answered but, is the ROM and the radio related in anyway say i have the stock fireware on the hero and the very latest radio would i still get the reception as if i was on the most current ROM?

[Guest stevenz]

This has probably been answered but, is the ROM and the radio related in anyway say i have the stock fireware on the hero and the very latest radio would i still get the reception as if i was on the most current ROM?

They're "mostly" separate.

A custom ROM (MoDaCo's at least) don't come with the Radio image included, the original RUU (ROM Update Utility) rom's do come with radio images. There's a bit of relation between the kernel (yet another component) and the radio, but not enough to worry about. If you can keep the original ROM and flash an up to date radio, then you should get any advantages of the updated radio without it affecting the rest of the system.

The main parts of a complete ROM are;

Recovery (Not included with MCR, but it is with some custom ROMs, and all original ones. Odds are anyone flashing MCR will probably be using the Amon Ra recovery image - The recovery gives full read/write access to the filesystem on the onboard memory, such as flashing custom ROM data & performing backups/restores, formatting etc. - Amon Ra is your friend here.

Boot (The linux kernel that does the hard work, anyone with MCR probably using Teknologist's modified kernel, and as of MCR 2.8, Tek's is standard)

System (The heart of the MoDaCo rom, this is the user-interface and the applications, most of the stuff you actually see & use, not user-modifiable)

Data (The "extra" stuff, settings, extra apps etc. Most of this stuff is user-writable via settings or installed apps)

Cache Just what it says.

System, Data and Cache are treated as separate partitions on the device, as is the SD-Card.

An official RUU ROM (and some non MoDaCo ROMs) will/may also include;

Radio (hardware interface drivers for WiFi, BlueTooth, GPS and the phone itself, basically handles all the over-the-air transmit/receive operations)

SPL (Secondary Program Loader - basically the bootsector for the phone, pretty much the most dangerous thing to mess with, if this goes wrong then the phone is dead. It instructs the phone how/what programs to boot into, such as the Recovery, Fastboot, or the Main OS. It also verifies the legitimacy of apps, so anything that goes on needs to be "signed" or it won't work unless the SPL is modified, see the stickies here, but basically, leave it alone!)

Splash (The bootscreen, see Paul's post elsewhere on this forum for how to modify this, all custom ROMs I'm aware of leave this alone, but I'm guessing MCR 3.1 may have Paul's nice MoDaCo logo in it).

Think I got this all correct, feel free to correct me though guys. Wow, I must be bored ;) Too windy for cycling to be fun ;)

Edited December 12, 2009 by stevenz