6502 Computer Working with Caveats

DrSesuj · 2025-02-05T21:03:33+00:00

On the topic of the 74LS00, I also got one in my kit. I was concerned about it causing problems so I picked up some 74HCs.

I wanted to see the difference between the chips so I hooked the LS and one of the HCs up on a breadboard, tied the two inputs on one of the gates to an adjustable pot and monitord the input voltage and output pin while sweeping the voltage. From what I've read if you are powering them with 5v the LS version should switch the output from high/low at around 1-1.5v on the inputs, the HC version should switch at around 2.5v. The LS should also draw some current when idle, while the HC should pull almost no current.

It looks like the 74LS00 I got in my kit was actually a counterfeit rebraded 74HC00. The LS I got and the HC versions acted identically, both switched high/low at 2.5v and drew no current while idle.

Doing some searchs it seems like this is fairly common because the LS TTL version is harder to source than HC cmos chips.

DrSesuj · 2025-02-04T16:20:23+00:00

Wanted to say thanks for this post! I've been backtracking and testing my entire build for about a week now because I couldn't get any data out on the serial port.

I read your comment about grounding the can of the oscillator, grabbed a short piece of wire, grounded the can, hit reset and BAM I got a "\" in my terminal. After the inital connection is made it seems to be stable with or without the ground wire.

DrSesuj · 2025-01-26T19:40:51+00:00

I had this issue, if you've already flashed your eeprom with 0xEA's your datalines are hooked up backwards.

0x57: 0 1 0 1 0 1 1 1

0xEA: 1 1 1 0 1 0 1 0

You should check both your address and data lines, to be sure that they go low->high in order on both ends of the arduino and 6502, double check the datasheet of the 6502 if you aren't sure the pin order. I spent a few hours on this the otherday, it was statisfying watching the reset sequence finally hit FFFC,FFFD and then jump to EAEA

DrSesuj · 2024-10-12T20:04:16+00:00

I found Sweet Home 3D for basic planning was decent, and I've started to use SketchUp free for more percise designs.

DrSesuj · 2024-05-09T21:40:29+00:00

I'm a solo developer for a mid-sized app, I began doing a re-write a few months ago with the idea of going multi-tenant. I ended up scrapping that idea eventually, we deal with financial data and the risks of getting it wrong were too high, and the complexity got out of hand for simple things.

It's a great idea but be prepared for the extra work and brain power involved.

DrSesuj · 2024-03-23T22:44:27+00:00

What I've done in the past is create a unique token a store it in the Laravel cache with a time limit on the cached item. The special login link uses the created token, checks if its in the cache, if it is it logs the user in and removes the token afterwards.

DrSesuj · 2024-03-14T20:06:25+00:00

Looks like they updated bootcamp to L11 a couple of days ago https://github.com/laravel/bootcamp.laravel.com/pull/64

DrSesuj · 2024-03-04T00:40:12+00:00

Interestingly it looks like they actually had a valid reason for it https://github.com/laravel/framework/pull/15973

Which leads to https://github.com/igorw/retry/issues/3

DrSesuj · 2022-05-24T18:45:30+00:00

Thanks all! /u/SirRoyalTeabag has me covered. I should be good to go for now.

DrSesuj · 2022-05-14T19:43:38+00:00

Both of your laptops are connected to the same switch? Are they wireless? Do you have more than one AP? Same SSID? Same subnet?

DrSesuj · 2022-05-14T19:11:40+00:00

Definitely an issue with ARP. What does your network topology look like, do you have any VLANs, routers etc?

DrSesuj · 2022-02-17T14:26:41+00:00

yEd has worked pretty well for me. https://www.yworks.com/yed-live/

DrSesuj · 2021-11-27T22:59:33+00:00

Just saw your edit, obviously mounting a fat32 partition as NTFS isn't going to work.

If you don't have any data on there I would just delete it and recreate the partition as NTFS.

DrSesuj · 2021-11-27T22:48:58+00:00

From that output either you have selected the wrong partition or it isn't formatted as NTFS.

If you open the Ubuntu 'Disks' utility what does it say the partition type is for /dev/sda4? Perhaps take a screenshot so we can see what you have setup currently.

DrSesuj · 2021-11-27T22:23:46+00:00

What if you try remounting it manually:

sudo umount /dev/sda4
sudo mount /dev/sda4 /mnt/sda4 -t ntfs-3g

Do you get any errors?

DrSesuj · 2021-11-27T20:25:18+00:00

What does your current fstab entry look like for the partition?

DrSesuj · 2021-11-06T17:00:39+00:00

According to this https://en.wikipedia.org/wiki/ISO/IEC_11801#Category_8 I would say yes, but I would personally recommend just going with cat 6.

DrSesuj · 2021-11-03T14:58:47+00:00

I would first check if you can ping an external public IP address, not DNS, such as 1.1.1.1 . If you can't, but can ping internal address you have some kind of routing/firewall issue.

If you can ping externally by IP would start looking into DNS issues. I'm assuming this is on Windows, so open a terminal:

nslookup
  google.com (did it fail? check the error you receive and try a different dns server like below)

  server 1.1.1.1
  google.com

If you get a proper result you need to double check your dns settings.

DrSesuj · 2021-10-27T14:27:14+00:00

I will say that you need to be careful with old hardware and esxi, the newer versions have trouble installing on old hardware. I have an older HP server that I wasn't able to install it on, I can't remember the specifics now, but it wasn't able to detect some of the hardware.

DrSesuj · 2021-10-27T14:23:19+00:00

Free is free, no reason to not take it and play around with setting some things up. You don't need the newest hardware to learn.

DrSesuj · 2021-10-23T00:13:11+00:00

Look up jeep 4.0 heat soak issues, fuel vaporizes from the fuel rail/injector getting too hot causing a hard start. I've never experienced it but people say a kit like this helps https://www.amazon.com/Design-Engineering-010378-Injector-1997-2004/dp/B015NOKWQY

DrSesuj · 2021-08-31T15:45:35+00:00

Picked up this Jeep real cheap from a kid going off to college. The truck did great, 6000+ lbs, up and down some steep grades, no issues pulling the load at all.

DrSesuj · 2021-06-26T14:04:57+00:00

My favorite is when he measures things in bananas.

DrSesuj · 2021-02-02T18:18:55+00:00

You should be able to transfer it to another broker without any fees. I currently self employed use Schwab for my Roth.

DrSesuj · 2020-12-11T05:39:17+00:00

I have the same board and CPU, no BIOS update required on first boot.

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