From mboxrd@z Thu Jan 1 00:00:00 1970 From: Stephan Linz Date: Thu, 4 Mar 2004 16:08:08 +0100 Subject: [U-Boot-Users] Proposal to add "ispeed" (I2C speed) command In-Reply-To: <20040304132105.AE2E8C0655@atlas.denx.de> References: <20040304132105.AE2E8C0655@atlas.denx.de> Message-ID: <04030416080802.12732@pcj86> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de Am Donnerstag, 4. M?rz 2004 14:21 schrieb Wolfgang Denk: > In message <04030413332001.12732@pcj86> you wrote: > > This 'could' be usefull to speed up the i2c communication if there are > > more than one i2c devices with significant differences between the clock > > timing; ex. 27C32 (100kHz at 3.3V) and LM75 (400kHz). Tolunay has spoken > > about like this. But right I see now reason to do so, too. U-Boot has to ^^^^^^^^^ OOPS, this was a small but fine typing error, should be: " ... But right I see _NO_ reason to do so, too. ... " (that's life) > > be a boot loader not a performant operator... > > Do you think it is legal to clock the I2C bus at 400 kHz when there > are devices on the bus that are spec'ed only for 100 kHz? I may be > wrong, but such an idea sounds awfully risky to me. You're right, see above :-) Best Regards, Stephan Linz