Rockbox.org home
release
dev builds
extras
themes manual
wiki
device status forums
mailing lists
IRC bugs
patches
dev guide



Rockbox mail archive

Subject: Re: external commands
From: [IDC]Dragon (idc-dragon_at_gmx.de)
Date: 2004-05-13


> I like the way it is defined, with a few tiny extensions:
>
> [IDC]Dragon wrote:
> > CD select buttons:
> > - 0xA0-0xA5 button n (1-6)
> > - 0xA6-0xAF reserved
>
> better (my head unit has got 10 direct disc buttons):
> - 0xA0-0xA9 button n (1-10)
> - 0xAA-0xAF reserved

That's what these "reserved" were for... ;-)

> > Inquiry commandos:
> > - 0xB0 give play status: state (changing, etc) (return payload: 2 byte
> > flags, tbd)
> > - 0xB1 give disk status: #of tracks (return payload: 16 Bit little
> endian)
> > - 0xB2 give current track # (return payload: 16 Bit little endian)
> > - 0xB3 give current track time (return payload: seconds as 16 Bit little
> > endian)
>
> still missing:
> - 0xB4 give track title (return payload tbd)
> - 0xB5 give artist name
> - 0xB6 give album title
> - 0xB7-0xBF reserved

Taking some more, eh? Well, that's what they are for. I hope my "grouping"
by the first hex digit holds.

> I'm not sure yet how the "return payload" should be handled for the text
> strings.

The generic response pretty much defines it:
Byte 1: negated command byte
Byte 2: number of chars
Byte 3...n-1: chars
Byte n: Checksum, 8-bit sum of bytes 1 to n-1

Jörg

-- 
NEU : GMX Internet.FreeDSL
Ab sofort DSL-Tarif ohne Grundgebühr: http://www.gmx.net/dsl

_______________________________________________ http://cool.haxx.se/mailman/listinfo/rockbox



Page was last modified "Jan 10 2012" The Rockbox Crew
aaa