Connecting an LCD to our computer — 6502 part 4
Here's a preview of the next installment in the 6502 series! Please take a look and let me know if you spot any issues or confusing parts.
I'm also open to better ideas for the video title and thumbnail. Content quality doesn't matter much if I can't entice people to click on the video in the first place. Did you learn something unexpected from this video?
Anyhow, as always, thank you for your support and please enjoy!
-Ben
Comments (26)
Really looking forward to the next video.... I will build up the full schematic beforehand though. Following along while also cutting, bending and assembling the wires is really tiresome.
It might be a good idea to reset the screen and home the cursor (reset the Address Counter) as part of the setup, because resetting the processor will have it write the string at the end of the current "Hello, World." It's not a big deal but I kinda of like watching the characters write in at 100hz.. :)
I was scratching my head trying to make the code better last night, until I remembered that I can't use subroutines without a stack and I can't have a stack without ram. Ugly code it is... for now.
Ben is such a master at "starting simple, add parts later". Having read books about those topics for 30 years, both for amateurs, students and pros - compared to all what I've read or seen, his YT videos are top notch :-) It's lovely to see the good old "burn and crash" method instead of fancy program loaders. Which might be a suitable next step to make debugging easier without plugging in/out the EEPROM... Looking forward to your next video!
Maybe but the code on your github. And see if anyone can come up with a solution or additions to the code. As others pointed out on comments on YouTube, you will need ram for JSR. But how much ? Just enough for the stack? I think it you could add a ps/2 keyboard. We could come up with a bare bones operating system for this computer. I have looked at the ps/2 datasheet. And I think a shift register and some decoding hardware/ software may work. I think I have a ps/2 female connector that I can connect to my bread board and I will see if I can interface it with a 6522. I will post here if I come up with any ideas that don't need too many components. And you have done another great series. Thank you and have a great new years
this is the PDF i came across: https://www.avrfreaks.net/sites/default/files/PS2%20Keyboard.pdf so my phase 1 will be making a (slow) clock and add an LED and see what comes out the data pin.
Great work Ben! I did not think that there will be another video this year :) (Since it can be quite stressful this time of the year) Have a great time! I'm very looking forward for the next video =)
Fantastically well thought out content with impeccable presentation as usual - thank you so much Ben. I don't know about others, but I could hear background humming/noise from about the 23:00 minute mark? Not serious, but I noticed it.
Excellent video. One note; I think it might be confusing for some how sending data to the screen works. I.e. you load data on the data pins and then you toggle the enable. I think it might help here to compare it with a latch or just a clock pulse in general and refer back to those videos to get the idea. There are so many steps just to set the LCD to the proper mode that the toggle instructions might overload some.
Was thinking the wiring looked sloppy, but then he poked at it for 1/2 second and then it was back to unattainable again. Missing a bit on understanding the E signal as it relates to datasheet, but might've missed that as there's too much going on at the moment (Christmas!).
Look at page 8 of the datasheet https://eater.net/datasheets/HD44780.pdf : E starts a data read/write cycle. Thus if you want to write to the LCD controller, you have to put the data on the data bus then bring E high.
Great video as always. The text appeared on the display quite slowly. I was wondering how much it could be speeded up, and what limitations there might be in that regard.
The clock generator in this video is only running at a few hundred hertz at most (you can see the LED flicker); it could be run at 2MHz and then the display would be written to much quicker.
Great update, well written and presented. I have no suggestions.
Great video. Good continuity and progression. As always, well done. Have a good festive season. (London and South Africa)
Excellent work Ben.... thanks.... very clear and concise.... just in time for Christmas, hope you have a Peacfull one....(and that goes to everyone else as well :-) )
Great video again, Ben. I’ve spent quite a few hours on the HD44780 and the explanation is well structured and fits the scope of the video well. The end felt a bit like a cliffhanger. ;) I look forward to the code optimisation.
This is very well done. Your step by step explanation made understanding a LCD module very clear.
Being from Belgium, it sometimes seems difficult to get the correct part. (Mouser, farnell) or a very high lead time for instance the LCD will only become available end of January. Ordering the kit overseas is a killer. For everything above 22€ (about) the belgian import is 22€ handling.
The display is very common so chances are you can find it in trashed electronics or surplus stores in Belgium. Otherwise Eckstein Komponente or Cheaptronic24 should have them in EU for 2-5€.
I thought it was well structured and presented. No suggestions 👍
For title maybe add 2x16 in there
I absolutely love this series
This is why I packed my breadboard for the holidays!
This is the best Christmas present, thanks Ben :)
Christmas came early!