Rockbox mail archiveSubject: Re: Another port, is it possible?
Re: Another port, is it possible?
From: Bluechip <csbluechip_at_gmail.com>
Date: Mon, 13 Aug 2007 20:07:00 +0100
>> > Most of the players have an Actions ATJ2085 CPU chip
>> > http://www.actions.com.cn/en/product.aspx?id=10 and can indeed
>> play OGG
>> > files (though their website doesn't say this)
>> I'd say that this CPU/microcontroller is the most limiting factor to get
>> Rockbox on these players: Rockbox is only built for and running on
>> 32 bit cpu
>> cores, so this Z80 8/16? bit will require some work to get Rockbox
>> for. We
>> once had it buildable for a 16bit CPU (calmrisc for one of the older
>> gmini models), but that particular port was abandoned and most of
>> the long/int
>> cleanups of those days are likely gone by now.
>The data sheet says 8bit! There is a DSP that does the MP3 decoding
>and a DMA controller, so most likely the z80 does little besides
>reading the FAT filesystem and setting up the DMA to pipe data from
>Flash to the DSP.
It also handles keyboard and screen, loads the dac into the dsp,
tells the radio what to do, and a few other trivial tasks.
Received on 2007-08-13