Memory test

[aspro648]

Having a bit of trouble wrapping my mind around the memory test.
When it "set in 13131" (Memory.tst line 48), and then "set load 1" (line 55), I'm seeing a dashed line in my screen:



That doesn't seem correct, and I am having trouble down the line with my ComputerRect-external.tst which I think is related.

I've seen a number of posts that seem to hint at this problem, but no definitive answer. Any help?

[cadet1620]

aspro648 wrote

Having a bit of trouble wrapping my mind around the memory test.
When it "set in 13131" (Memory.tst line 48), and then "set load 1" (line 55), I'm seeing a dashed line in my screen:
Here is my logic:
                Xor(a=address[13], b=address[14], out=screen);

13131 = 0x334B = 0011 0011 0100 1011 binary which should be a RAM address.
Your code sets screen true which causes the failure.

Please edit your post to remove the mostly functional code after the problem is resolved.

--Mark

[aspro648]

Off by 1 bit. The story of my life.

The different bus widths are confusing, but I can glimpse the elegance of the underlying structure of the overall memory arrangement.

I've been wondering what advantage the 16-bit scheme vs 8-bit makes the increased complexity worth it.

Thanks for getting me over the hump.

[rahiba]

When we running memory.hdl it shows a command like this. Please give us a solution.

[cadet1620]

You need to select "Screen" from the "View" menu. Then you will see the Keyboard icon that is mentioned in this message.



--Mark

[Jane Wu]

Hi.Mark
 I also met this problem,and I have used the Keyboard chip instead of the common register.
 I have found the keyboard icon,but when I held down the "K",it still can't run the next instruction.

 is there anything wrong in my HDL file?

[Jane Wu]

I replaced the 8KRAM with the Screen chip,i still didn't work,

[cadet1620]

I can see in your screen shot that part2 is 75 which is the 'K' key, but out is 0.

The test is reading the keyboard address and waiting for out to be 75 before continuing.

Check the HDL that routes part2 to out when address = 24576 (0110 0000 0000 0000 binary).

--Mark

[Jane Wu]

Hi,Mark
 thanks for your help, I have solved my problem.The reason why I made the mistake is that I did't choose the correct sel needed by the MUX/DMux to select the targeted chips.
Jane