Ivan, You should check again the QBLT usage<http://processors.wiki.ti.com/index.php/PRU_Assembly_Instructions#Quick_Branch_if_Less_Than_.28QBLT.29>.
The code will stay in your loop when rT2 < rT1 i.e. IEPcount < 1. Try QBLT L1, rT2, rT1 Regards, Thomas On Wednesday, October 2, 2013 10:07:33 AM UTC+2, Ivan Korman wrote: > > Hm, I have to correct my self. After throwing a second look into > instruction format for quick arithmetic test and branch, where register is > Op2, QBNE supports comparisons of all bits in both registers (didn't read > tables Rs2Sel and Rs1Sel to the end). My mistake... > > Yet, this than makes my first code not working even a bigger misery. Will > have to take a much deeper look at the code. > > Ivan > > On Wednesday, October 2, 2013 9:44:18 AM UTC+2, Ivan Korman wrote: >> >> Thx. I already found example you mention (glad to know it's yours) and >> used it as guideline how to use compare registers on IEP. Did reworked the >> example and now it's running fine. I suspect that issue in my initial >> example was with following piece of code >> >> L1: >> LBBO rT2, rIEPBase, IEP_COUNT, 4 >> QBLT L1, rT1, rT2 >> >> My expectation was that "quick branch" instructions does comparison of >> complete registers (all 32 bits), but in fact it compares only 8 bits (you >> can chose if it's B0,B1,B3 or B4). In my case I think it was working only >> rT1.b0 and rT2.b0. For sure that contributed to unexpected execution flow, >> maybe there was also something else. >> >> Although reworked example works just fine, will debug this one as I don't >> want to leave open ends :) Also will try debugger you mentioned, as writing >> apps blindly and debug them only with LED attached to GPIO is bit of pain :) >> >> Thx >> Ivan >> >> >> On Wednesday, October 2, 2013 12:16:58 AM UTC+2, Charles Steinkuehler >> wrote: >>> >>> >>> I don't immediately see anything obvious that is wrong with your code. >>> >>> I have a known working example of using the IEP timers with the PRU, but >>> I'm using the overflow event rather than polling the count value: >>> >>> >>> https://github.com/cdsteinkuehler/linuxcnc/blob/MachineKit-ubc/configs/ARM/PRU-Debugger/pruexample.p >>> >>> >>> >>> -- >>> Charles Steinkuehler >>> [email protected] >>> >>> -- For more options, visit http://beagleboard.org/discuss --- You received this message because you are subscribed to the Google Groups "BeagleBoard" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/groups/opt_out.
