Exercise - PWM compared with
PPM
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Last updated:
24-08-09 |
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Based at Clk = 50 MHz |
Sw7
Scale |
Sw3 .. Sw0
PCM |
Ld4
PPM |
Ld3
PWM |
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0 |
0 0 0 1 |
Blinking |
Blinking |
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1 |
0 0 0 1 |
Dimmed 1/16 |
Dimmed 1/16 |
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0 |
0 1 0 0 |
Dimmed 4/16 |
Blinking |
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1 |
0 1 0 0 |
Dimmed 4/16 |
Dimmed 4/16 |
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0 |
0 1 0 1 |
Dimmed 5/16
and Flickering (strange) |
Blinking |
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1 |
0 1 0 1 |
Dimmed 5/15 |
Dimmed 5/16 |
| Please try
all combinations you like in order to watch the difference
between PWM and PPM |
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(1)
Calculate the estimated frequencies which Ld4
and Ld3 will be controlled by - in order to solve this must you
study the Clock_scale process below.
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(2)
Write you own version of the code for a PWM
generator.
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(3) Write you own version of the
code for a PPM generator.
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(4) Create a Test Bench which
test all PCM combinations (like shown under hints)
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