From mboxrd@z Thu Jan 1 00:00:00 1970 To: <9fans@9fans.net> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Date: Tue, 26 Oct 2010 17:17:11 -0500 From: EBo In-Reply-To: References: <06fed67ccccb147c7e18240205ff0ca0@quintile.net> <1b5a7cf45e8c570c416d1d08b607bb35@swcp.com> Message-ID: <0989b27ff533c15ead7c86810a6a4171@swcp.com> User-Agent: RoundCube Webmail/0.4-trunk Subject: Re: [9fans] JTAG Topicbox-Message-UUID: 6e6ed8a2-ead6-11e9-9d60-3106f5b1d025 Gorka, This all sounds good. I wish you luck... EBo -- > The way I think this works: > > USB-MPSSE-JTAG-uP > > The USB part is a simple protocol which I already have figured out > and is > in the driver's .h. > http://yosemitefoothills.com/Electronics/FTDI_Chip_Commands.html > > I am now looking into the MPSSE details which is a > kind of programmable controller for the JTAG which has high level > commands > so that operations do not take a round trip through USB. > > For this the best docs I found are the openocd code and some > documents > referred in it: > http://www.ftdichip.com/Documents/AppNotes/AN2232C-01_MPSSE_Cmnd.pdf > http://openocd.berlios.de/web/ > > The openocd code is my main reference because it does work on linux. > If I have to I'll resort to sniffing the USB connection in linux, > though I hope > it does not come to that. > > After the MPSSE (or at the same time) > I have to figure the JTAG part for which probably EBo's references > are good, > I haven't figured that part at all. Then there is an standard for > arm called ICE something or other (apparently there are different > names and > interfaces for different versions of arm) which lets you look at the > different > registers of arm and do interesting things to it. Then there is how > the JTAG is > cabled inside the SoCer itself: > > > http://www.marvell.com/products/processors/embedded/kirkwood/HW_88F6281_OpenSource.pdf > > I am working my way slowly through this sorry if this a tad > incoherent, but I haven't > figured most of it yet. > > G.