On Wed, May 27, 2009 at 01:08:19PM +0200, Hans de Goede wrote: > > > On 05/27/2009 11:15 AM, Andre Prendel wrote: >> Hi Hans, >> >> looking in the datasheet of the TMP421 sensor chip >> >> http://focus.ti.com/docs/prod/folders/print/tmp421.html, >> >> I saw the following addresses. >> >> TMP421 100 11xx >> TMP422 100 11xx >> TMP423A 100 1100 >> TMP423B 100 1101 >> >> But the preliminary driver of your students uses 0x2a. >> >> /* Addresses to scan */ >> static unsigned short normal_i2c[] = { 0x2a, I2C_CLIENT_END }; >> >> 0x2a == 010 1010b, right? >> > > Right. > >> Do I misunderstand something? > > No, what my students did in there was wrong, they only put the > address in there to which the sample I gave them is wired > > The addresses to scan should be: > static unsigned short normal_i2c[] = { 0x1c, 0x1d, 0x1e, 0x1f, > 0x2a, 0x4c, 0x4d, 0x4e, 0x4f, I2C_CLIENT_END }; > > But we better run those past Jean, to see if any of > those are dangerous to scan by default, Jean ? > >> And what means the xx in the address of TMP421/422? > > This means that the address is configurable by hooking up > the IC in different ways, see table 9 and 10 at page 17 of > the data sheet. Thanks, I didn't see this so far. Now I understand :) > > Regards, > > Hans Andre
