Hello, please can somebody help me this circuits cpu to connect with display and keyboard

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The "computer" he's trying to build uses a very specific bit-to-pixel mapped output. It would need the operating system rewriting to use any other form of display.

The only practical physical version recreation of the original HDL emulator I can think of is by using a dual-port RAM with the output side driven from counters using timing taken from a video sync generator circuit.

There are various more practical designs available for DIY machines, that can be built with completely off the shelf parts & no great hassle, as there will be with this.. Though I've got to admit it would be quite impressive to see it realised entirely in physical logic!
 
thank you very much, i read fast is so beatifull book(good explained, +info), o my friend now one week i am seraching
thank you very muchh, i read fast is such tutorial
 
michael1978 said:
thank you very much, i read fast is so beatifull book(good explained, +info), o my friend now one week i am seraching

thank you very muchh, i read fast is such tutorial
Click to expand...
ooo sorry i send 2 times, something wrong with my interent, like i say, i search on the internet i found nothing good, i have just one more quesion now i know how to generate signal and timing, you know the information come out the RAM, but how do i get the generator circuit about vsync and hsynsc where? there are only 16pixel of informaion out of memory? thanks one time have a nice sleep
 
sorry this doual-port RAM, i have to connect with signale of RAM output and video sync generator right?
 
unclejed613 said:
there's this kit https://gigatron.io/
that does a CPU and graphics with TTL chips. the kit is 149.50 euros
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ooh my gigatron 8 bit guy, i have in my home i buy , but i dont find nothing intersting when i dont know how it works how its programming
this course nand2tetris is perfect if he explaing all everything, because you learn new thing for example how to build how to programming, so you have learn compiler assembler pc, sooo in the futur you know everything how si going….good night
 
michael1978 said:
sorry this doual-port RAM, i have to connect with signale of RAM output and video sync generator right?
Click to expand...

If you look at the signals connecting to the "screen" block, they are the same as with the RAM block, except at a different address area (SelScr rather than SelRAM from the address decoder block).

The CPU stores the pixel data in RAM, but a different block or unit of RAM to the normal working memory.
Note that the address bus is connected to the screen to control what word of the screen RAM is written or read.


In the simulator, the screen RAM is mapped to visual pixels by software.
To do it in hardware, you need dual-port RAM that can be read independently with timing synchronised to the required video sync signals.

eg. The column counter (something like in my testcard circuit) addresses pixels across the screen. For your display, you could use the lowest four bits to address a 16 way multiplexer which selects one but from the addressed word as output, then the rest of the bits of the column count become then low address to the RAM.

512 pixels / 16 bits = 32 words; 5 bits address for the column address of a word within one pixel row.

The next 8 RAM address bits are the row address, to give the full 512 x 256 pixel screen.
 
HI
i build like i understand you a 16 way MUX, so i did like you say

sorry what come next to circuit i build
something to adress memor spmething to output mux
where the dual - RAM where to connecte to adress memory or out from mux, and generatoroutput from mux or adress memory
please help to build this circuits(we are almost finish;--)
 
michael1978 said:
we are almost finish;--)
Click to expand...
You are a VERY long way from finished!

You would need to build the whole clock generator, sync timing and column / row counter system, just to start with.

You still have not posted any photo of actual _physical_ builds of parts, that you earlier said you had breadboarded.
 
Hello
sorry for my late answer
i (hope) will put the photo tomorow… because of time

i read a book
i try to study your book in page 25
i try to decode ;-)
like i read that book and your schematic i see
that you need a clock, counter, ram generator, shift register and finish result
i do experiments in proteus(is my first time that i use)
greetings
 
hello
here what i work
i am gonna make your circuit for display controller ;-)))) he goona work for my processor?(
i try to understand and to build, when i gonna build i gonna send you email right ) ohh Goodnight.....​
 
You need spaces between the sockets - some IC bodies are too long to fit with the pins. Gaps are also useful as wiring "lanes" so the connections you add are not crossing other solder joints - or places you will need to add more connections to later.

Also you have all 18 pin 0.3" pitch, no allowing for the different size ICs.
You need to fully plan things and work out the exact IC types (and packages), plus allowing for other components, before you start building.

This is a practical example, though built with wire-wrap. There are decoupling capacitors under every IC, hidden inside the IC sockets.
The ICs are set out with reasonable spacing, on a ground-plane board to avoid electrical noise.

https://flic.kr/p/JHgJwf
 
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