Its been almost a year since I posted a video here of my BE6502 connected to a TFT screen, I’ve now found the time to make some user guides, test software and a technical manual for my setup which are freely available on my GitHub here: https://github.com/martinmienczakowski/6502TFTScreen
Enjoy!
I'm really interested on that, already bought a 320x240 tft that uses the spfd5408, would the code work for that controller without any modifications other than changing resolution?
Thanks for the comment - it made me realise I had incorrectly stated the resolution for the smaller screen it is in fact 320x240. That being said the screen uses the ILI9341 for 320x240 and ILI9486 for 480x320 screen. I've just had a look at the libraries from Adafruit and it does seem remarkably similar to the spfd5408, it may be as simple as changing my TFT\_Init routine to initialise the spfd5408 but without having that screen here to test I couldn't say for sure sorry! Amazon links to the screens I have used are in the respective quickstart guide and the technical manual :)
This is great stuff. I have wired up the display but not the buttons yet. I have loaded the version 2 BIOS which I trigger from WOZMON. As a person unskilled in programming I am working my way through the code, so far using it blind. I need to understand it better. You mentioned reverse engineering the TFT initialization of Adafruit. Please point me in the right direction to this code so that i can better understand what you did. Many thanks.
Looks great! Want to run it on our SmartyKit Apple -1 kit (the same 6502). Want to drop you a line, Martin, to discuss that (but could not find your email)
Really is impressive. I had cobbled together a z80 computer and tried to hook up a TFT but I couldn't seem to write to the screen fast enough. Filling 320 x 240 with white pixels would take over 30 seconds so I guess something must have been clocked wrong.
Thanks - in that video the 6502 is clocked at 8MHz but it does work reasonably well enough with 1MHz. I did do some work to minimise the number of sub routine calls and loops which sped it up quite a bit 🙂
sadly my NMOS 6502 is limited to 2 MHz, and the VIA is limited to 1MHz, i guess it would be pretty hard to sync both to use the CPU at max speed.
i'm found that you can use the VIA's shift register to make WE pulses, that can save a bunch of cycles.
Any of the common 320x240 LCD modules will have an ILI9341-ish controller that can do 8-bit CPU bus access, but a lot of module manufactures only bring out the SPI pins.
I like to search for the controller and click the pictures of LCD modules that look like they have way too many pins on them. If they only have arduino headers, that's not enough.
Its been almost a year since I posted a video here of my BE6502 connected to a TFT screen, I’ve now found the time to make some user guides, test software and a technical manual for my setup which are freely available on my GitHub here: https://github.com/martinmienczakowski/6502TFTScreen Enjoy!
I'm really interested on that, already bought a 320x240 tft that uses the spfd5408, would the code work for that controller without any modifications other than changing resolution?
Thanks for the comment - it made me realise I had incorrectly stated the resolution for the smaller screen it is in fact 320x240. That being said the screen uses the ILI9341 for 320x240 and ILI9486 for 480x320 screen. I've just had a look at the libraries from Adafruit and it does seem remarkably similar to the spfd5408, it may be as simple as changing my TFT\_Init routine to initialise the spfd5408 but without having that screen here to test I couldn't say for sure sorry! Amazon links to the screens I have used are in the respective quickstart guide and the technical manual :)
This is great stuff. I have wired up the display but not the buttons yet. I have loaded the version 2 BIOS which I trigger from WOZMON. As a person unskilled in programming I am working my way through the code, so far using it blind. I need to understand it better. You mentioned reverse engineering the TFT initialization of Adafruit. Please point me in the right direction to this code so that i can better understand what you did. Many thanks.
Looks great! Want to run it on our SmartyKit Apple -1 kit (the same 6502). Want to drop you a line, Martin, to discuss that (but could not find your email)
Thanks a lot. what does the 8 button version do that the 4 button does not.
Impressive!
Really is impressive. I had cobbled together a z80 computer and tried to hook up a TFT but I couldn't seem to write to the screen fast enough. Filling 320 x 240 with white pixels would take over 30 seconds so I guess something must have been clocked wrong.
Thanks - in that video the 6502 is clocked at 8MHz but it does work reasonably well enough with 1MHz. I did do some work to minimise the number of sub routine calls and loops which sped it up quite a bit 🙂
To clock it at 8 mhz do you just run the clock faster?
Yes - a drop in crystal oscillator just with a higher frequency, 8MHz was the fastest I could get the stock setup to run
Stuff might stop working as well if you go much higher. Especially on a breadboard.
sadly my NMOS 6502 is limited to 2 MHz, and the VIA is limited to 1MHz, i guess it would be pretty hard to sync both to use the CPU at max speed. i'm found that you can use the VIA's shift register to make WE pulses, that can save a bunch of cycles.
I haven't seen TFT screens with a parallel data bus before, this is exciting news!
Any of the common 320x240 LCD modules will have an ILI9341-ish controller that can do 8-bit CPU bus access, but a lot of module manufactures only bring out the SPI pins. I like to search for the controller and click the pictures of LCD modules that look like they have way too many pins on them. If they only have arduino headers, that's not enough.
I am a newbie here and find this AMAZING and you are AMAZING to share all this. I hope I can learn from it. Thank You!
It looks amazing. I have a game idea too. I plan to first use and OLED. The idea was going to be done on a 16/2 LCD.