On 15.08.2016 21:42, Maarten Brock wrote: >> On 15.08.2016 20:54, Maarten Brock wrote: >>>> On 15.08.2016 20:01, Philipp Klaus Krause wrote: >>>>> Hello, >>>>> >>>>> I wrote my first little mcs51 program today, for the Cypress FX2LP. >>>>> But >>>>> I encountered a problem: Timer 1 runs too fast. When I set up Timer 0 >>>>> and Timer 1 the same, Timer 1 runs about 4 times faster. >>>>> >>>>> I first noticed the problem when trying to do a software UART, which >>>>> worked with Tiemr 1, but not with Timer 2. >>>>> >>>>> I have attached programs for a 2-bit counter on the LEDs of my board a >>>>> bits 0 and 1 of port A. With Timer 1, the counter increments once per >>>>> second. >>>> >>>> The previous two paragraphs were meant to be: >>>> >>>> I first noticed the problem when trying to do a software UART, which >>>> worked with Tiemer 0, but not with Timer 1. >>>> >>>> I have attached programs for a 2-bit counter on the LEDs of my board a >>>> bits 0 and 1 of port A. With Timer 0, the counter increments once per >>>> second. >>>> >>>>> I compile my programs using >>>>> sdcc -mmcs51 test2.c >>>>> and put them onto the FX2LP using >>>>> cycfx2prog prg:test2.ihx run >>>>> >>>>> Philipp >>> >>> Hello Philipp, >>> >>> You did not set CKCON which selects the prescaler clk/4 or clk/12. T0M >>> and T1M should be 0 after reset, but the loader may have left them >>> differently. >>> >>> Maarten >> >> I didn't set it. But by setting it I can make the timer run even faster. >> >> Philipp > > Then maybe you didn't clear TMOD.2 (C/T0) when using timer 0? Then you > would be counting whatever happens on T0. > > Maarten
The problem was indeed a wrong TMOD setting. I was running in 13-Bit timer mode for timer 1, while using 16-but timer mode for timer 0. Philipp ------------------------------------------------------------------------------ What NetFlow Analyzer can do for you? Monitors network bandwidth and traffic patterns at an interface-level. Reveals which users, apps, and protocols are consuming the most bandwidth. Provides multi-vendor support for NetFlow, J-Flow, sFlow and other flows. Make informed decisions using capacity planning reports. http://sdm.link/zohodev2dev _______________________________________________ Sdcc-user mailing list Sdcc-user@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/sdcc-user
