Let's make a Pi Pico 2 powered video card.
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Right. This isn't completely baffling or anything
Oh, wait, I remember this level from ZZT.
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Oh, wait, I remember this level from ZZT.
I think the elf needs food badly
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I think the elf needs food badly
okay this isn't that confusing
for example, these are the snake pins. you can choose from left snakes or right snakes
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Right. This isn't completely baffling or anything
@gloriouscow this seems like something @paulrickards would generate and send to his plotter
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I'm starting to think a pico is not the appropriate thing to build a video card with.
all my fun ideas always end up with me concluding i should use an FPGA.
FPGAs are like the crabs of electronics projects. everything wants to turn into an FPGA if you give it enough time.
@gloriouscow are DSPs horribly unfashionable now? I remember for a minute in the 90s, everything was a DSP
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@gloriouscow this seems like something @paulrickards would generate and send to his plotter
@robdaemon @gloriouscow Totally, I'd plot that
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okay this isn't that confusing
for example, these are the snake pins. you can choose from left snakes or right snakes
you know, there's a very good reason NOT to use an FPGA
when you actually use the proper tools for a job, it stops becoming a hack.
you're no longer a hacker, you're some kind of engineer or something. ugh.
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you know, there's a very good reason NOT to use an FPGA
when you actually use the proper tools for a job, it stops becoming a hack.
you're no longer a hacker, you're some kind of engineer or something. ugh.
Well, I did an FPGA thing. Can check that off the bucket list.
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okay this isn't that confusing
for example, these are the snake pins. you can choose from left snakes or right snakes
@gloriouscow this pin only does rising edges
That pin only does falling edges
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Well, I did an FPGA thing. Can check that off the bucket list.
“That's why they call me the Count!” —you, probably
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“That's why they call me the Count!” —you, probably
@argv_minus_one nobody has ever called me the count, and i hope they do not start
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Well, I did an FPGA thing. Can check that off the bucket list.
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Well, I did an FPGA thing. Can check that off the bucket list.
Okay, lets see if I can get a 14.31818MHz clock out of this thing.
We have a 50MHz clock source, on a pin called FPGA_CLK1_50.
How do we get 14.31818MHz out of that?
By attaching a PLL to it, hopefully.
module de10_clock_test (
input wire FPGA_CLK1_50,
output wire GPIO_1_0
);
wire clk_osc;
wire pll_locked;
cga_pll pll_inst (
.refclk (FPGA_CLK1_50),
.rst (1'b0),
.outclk_0 (clk_osc),
.locked (pll_locked)
);
assign GPIO_1_0 = clk_osc;
endmodule -
Okay, lets see if I can get a 14.31818MHz clock out of this thing.
We have a 50MHz clock source, on a pin called FPGA_CLK1_50.
How do we get 14.31818MHz out of that?
By attaching a PLL to it, hopefully.
module de10_clock_test (
input wire FPGA_CLK1_50,
output wire GPIO_1_0
);
wire clk_osc;
wire pll_locked;
cga_pll pll_inst (
.refclk (FPGA_CLK1_50),
.rst (1'b0),
.outclk_0 (clk_osc),
.locked (pll_locked)
);
assign GPIO_1_0 = clk_osc;
endmodulepll_instis a PLL instantiation. But notice it says nothing about like dividers or anything. We have to go into something confusingly called the IP (Incendiary Pickle) Catalog to actually configure the PLL.This is far as a I get because doing this causes Quartus to hang.
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pll_instis a PLL instantiation. But notice it says nothing about like dividers or anything. We have to go into something confusingly called the IP (Incendiary Pickle) Catalog to actually configure the PLL.This is far as a I get because doing this causes Quartus to hang.
Oh wait I just had to wait seventeen minutes. cool.
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Oh wait I just had to wait seventeen minutes. cool.
i bet there are people reading this that know how to actually use this stuff and are having themselves a sensible chuckle at my expense
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i bet there are people reading this that know how to actually use this stuff and are having themselves a sensible chuckle at my expense
when you build the PLL you get a QIP file full of nonsense
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when you build the PLL you get a QIP file full of nonsense
Okay, if I did all this right, i should have a 14.31818MHz clock on GPIO pin 1.
Let's find out! To the workbench!
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@bytex64 just out of curiosity what's the derivation of that how how did you drive it with a pico?
@gloriouscow IIRC it’s the regular fractional divider PWM mode but it was a while ago. I do have the source for it: https://github.com/bytex64/tt-munch/tree/main/clockgen
It’s also not super exact. IIRC the closest it could get was like 25.150 or something.
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Right. This isn't completely baffling or anything
@gloriouscow you won minesweeper!
