Ok, I have GOT to be doing something wrong...

Ok, don't really need to post code, but there HAS to be something I am doing wrong here... Played with my Parallax Professional Dev Board Rev B, cause I needed to see if it functions. Apperently the Pulse Gen is just bad then, cause the BS2pe is recognized, programs n works. Tested using a VERY simple program, but the part I am confused with is FREQOUT pin, Duration, Freq1, Freq2 In my case its Freqout 10, 1000, 852. Hooked up to my Multifunction Counter. Now I know that 852*(1/1.51) = like 564 is what I should use to get a freq of 852hz, which i tried. now both my Multifunction Counter as well as my Digital Multimeter with Freq n duty options BOTH read the same and its WAAAAAAAAY the heck off I read like 65Khz.... I tried my Oscilloscopes probe to see if it's a case o bad probe, but same results, tried creating same desired 852 hz on a BS2 Homework board, thinking something was wrong with the BS2pe, but NOPE, waaaaaaaayyyyyy offf again this time like 39Khz, this was the first time I even used the BS2 HW board, so there's no way possible its damaged. So I am litterally confused WHAT the issue(s) are... I know what I should see on the counter is 0.852ish Khz, but it's not even in the same planet let alone the ballpark.... The Multifunction Counter came from Chris Savage, so I KNOW the instruments have to be correct, plus even if there was errors in one, why would 2 diff instruments give same reading.... Though my DMM did read off like 5-10Khz, but after playing with Counter buttons got them reading the same so ANY ideas WHAT the issue is????? Ground of Test probe to ground/neg terminal and other straight to signal wire, on IO 10.... I am really confused on this one. I know I haven't touched my electronics in like 2-3 years, but I know I ain't this rusty...... Thanks in advance for ANY help.

Joe

BTW code litterally just, minus the lang n chip settings of course

DO
FREQOUT 10, 1000, 852
LOOP
~Owner, Designer & Builder Killer K.A.R.R.
~Starfleet Captain Joe R.
Current Commission: USS-Titanic Registry Number NCC-1513
Launched: Star Date 48509.9 April 10th, 2385
Galaxy Class, Titanic Sub-Class Starship Max Warp: 15.96

Comments

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  • FREQOUT generates the tones using high frequency PWM and needs a filtering circuit at the output to eliminate the PWM frequencies. See page 200 of the Basic Stamp Reference Manual.

    "The circuits in Figure 5.6 work by filtering out the high-frequency PWM
    used to generate the sine waves. FREQOUT works over a very wide range
    of frequencies (as shown in Table 5.26) so at the upper end of its range,
    those PWM filters will also filter out most of the desired frequency. You
    may find it necessary to reduce values of the parallel capacitors shown in
    the circuit, or to devise a custom active filter for your application.
    "
    Florida, between St. Petersburg and the Gulf of Mexico

    Do not look directly into laser with remaining good eye...
  • Ok, so its not me then. Ok, so need to figure out how to check the freq for my project.. Thanks for the help. Clears up whats going on.

    Joe
    ~Owner, Designer & Builder Killer K.A.R.R.
    ~Starfleet Captain Joe R.
    Current Commission: USS-Titanic Registry Number NCC-1513
    Launched: Star Date 48509.9 April 10th, 2385
    Galaxy Class, Titanic Sub-Class Starship Max Warp: 15.96
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