Kristof, Sorry to sound like a broken record, but this is all in the datasheet. See, for example, here:
http://datasheets.maximintegrated.com/en/ds/DS1921H-DS1921Z.pdf You cannot change mission parameters while a mission is active (rollover, for example). This must be done when no mission is active. The parameters are read-only during a mission. "Running" I assume refers to the Mission In Progress parameter, which you may write zero to to stop a mission, but cannot write 1 to to start one (this is done with Enable Mission). See pages 9 and 14 of the datasheet for help starting a mission, and page 36 for a stepwise example. Colin On 12/11/2014 17:32, Csillag Kristof wrote: > OK, so here is some feedback. > > I can confirm that writing a value to Easystart starts a measurement: > - It sets delay to 0 > - It set frequency to the same value that was written to Easystart > - It clears previous samples > - It clears rollover > - It starts the mission. > - (It probably also starts the clock, but I can't confirm that, > because I started it already manually.) > > I have one problem though: I can't seem to be able to figure out how to > start a measurement with rollover. > - Easystart starts is w/o rollover. > - If I just enable rollover, it stops the running mission. > - If I simply try to launch the mission by any of the intuitive ways, > it won't start. > (I am trying these: > - writing 0 to delay > - writing a value into frequency > - writing YES into running > ) > > So I guess there is a sequence of things I must to to start a > measurement with rollover... > > Any help would be appreciated. > (Next thing I will do, I'll look at the source code for easystart to > figure out the sequence for rollover.) > > Kristof > > > On 2014-12-09 01:58, Paul Alfille wrote: >> >> Yes. Easystart is a convenience function. Otherwise there are a number >> of steps needed in sequence to start a measurement and a risk of >> bricking the device if the oscillator isn't started first. I'll admit >> I haven't looked at the thermochrons in some years so testing would be >> wise (and feedback welcome). >> >> On Dec 8, 2014 3:10 PM, "Jan Kandziora" <j...@gmx.de >> <mailto:j...@gmx.de>> wrote: >> >> Am 08.12.2014 um 19:14 schrieb Csillag Kristof: >> > On 2014-12-08 18:35, Colin Reese wrote: >> >> Check the datasheet. These parameters are well-documented. >> > >> > I tried to. >> > >> > I looked at http://datasheets.maximintegrated.com/en/ds/DS1921G.pdf >> > >> > It does not seem to contain the word "easystart". >> > >> >From owfs/module/owlib/src/c/ow_1921.c: >> >> static ZERO_OR_ERROR FS_easystart(struct one_wire_query *owq) >> { >> /* write 0x020E -- 0x0214 */ >> BYTE data[] = { 0x86, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, }; >> >> /* clear memory */ >> RETURN_BAD_IF_BAD( OW_clearmemory(PN(owq))) ; >> >> /* Stop clock, no rollover, no delay, temp alarms on, alarms >> cleared */ >> if ( BAD( OW_w_mem(data, 7, 0x020E, PN(owq)) ) ) { >> return -EINVAL; >> } >> >> return GB_to_Z_OR_E( OW_startmission(OWQ_U(owq), PN(owq)) ); >> } >> >> >> When easystart is written (anything), this function writes clears the >> chip memory and writes 0x86, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 into >> 0x020e at further. >> >> It sets -EOSC, TLS, THS in the control register and clears the >> temperature, start delay and status registers. >> >> Kind regards >> >> Jan >> >> >> ------------------------------------------------------------------------------ >> Download BIRT iHub F-Type - The Free Enterprise-Grade BIRT Server >> from Actuate! Instantly Supercharge Your Business Reports and >> Dashboards >> with Interactivity, Sharing, Native Excel Exports, App Integration >> & more >> Get technology previously reserved for billion-dollar >> corporations, FREE >> >> http://pubads.g.doubleclick.net/gampad/clk?id=164703151&iu=/4140/ostg.clktrk >> _______________________________________________ >> Owfs-developers mailing list >> Owfs-developers@lists.sourceforge.net >> <mailto:Owfs-developers@lists.sourceforge.net> >> https://lists.sourceforge.net/lists/listinfo/owfs-developers >> >> >> >> ------------------------------------------------------------------------------ >> Download BIRT iHub F-Type - The Free Enterprise-Grade BIRT Server >> from Actuate! Instantly Supercharge Your Business Reports and Dashboards >> with Interactivity, Sharing, Native Excel Exports, App Integration & more >> Get technology previously reserved for billion-dollar corporations, FREE >> http://pubads.g.doubleclick.net/gampad/clk?id=164703151&iu=/4140/ostg.clktrk >> >> >> _______________________________________________ >> Owfs-developers mailing list >> Owfs-developers@lists.sourceforge.net >> https://lists.sourceforge.net/lists/listinfo/owfs-developers > > > > ------------------------------------------------------------------------------ > Download BIRT iHub F-Type - The Free Enterprise-Grade BIRT Server > from Actuate! Instantly Supercharge Your Business Reports and Dashboards > with Interactivity, Sharing, Native Excel Exports, App Integration & more > Get technology previously reserved for billion-dollar corporations, FREE > http://pubads.g.doubleclick.net/gampad/clk?id=164703151&iu=/4140/ostg.clktrk > > > > _______________________________________________ > Owfs-developers mailing list > Owfs-developers@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/owfs-developers > ------------------------------------------------------------------------------ Download BIRT iHub F-Type - The Free Enterprise-Grade BIRT Server from Actuate! Instantly Supercharge Your Business Reports and Dashboards with Interactivity, Sharing, Native Excel Exports, App Integration & more Get technology previously reserved for billion-dollar corporations, FREE http://pubads.g.doubleclick.net/gampad/clk?id=164703151&iu=/4140/ostg.clktrk _______________________________________________ Owfs-developers mailing list Owfs-developers@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/owfs-developers
