Hi,
I'm looking to connect 2 Vics over the Userport, I've read the same sections in the Programmers Ref Guide too. Would you be kind enough to share your code from your arduino project? Might help me make some progress faster.
Thanks
Search found 34 matches
- Sun Sep 22, 2024 6:28 am
- Forum: Programming
- Topic: Bi-Directional User Port Code
- Replies: 6
- Views: 6697
- Fri Mar 01, 2024 10:24 am
- Forum: Emulation and Cross Development
- Topic: Emulation of RS232 VIC20 for running multiplayer games
- Replies: 34
- Views: 25069
Re: Emulation of RS232 VIC20 for running multiplayer games
Ok, well, I built my cable last weekend, so I'll do some more reading and give this a try.
- Wed Feb 21, 2024 9:21 am
- Forum: Emulation and Cross Development
- Topic: Emulation of RS232 VIC20 for running multiplayer games
- Replies: 34
- Views: 25069
Re: Emulation of RS232 VIC20 for running multiplayer games
Building the connection cable is easy. 1. get a normal stereo audio cable (two lines plus the ground) and two connectors for the RS232 port. 2. Mark each connector with a label "TOP SIDE" just to avoid confusion later 3. Solder the ground of the cable to the A pin of both connectors. 4. C...
- Thu Oct 19, 2023 9:58 am
- Forum: Programming
- Topic: Keyboard Input in Assembly - advice sought
- Replies: 14
- Views: 6145
Re: Keyboard Input in Assembly - advice sought
Thanks for the pointers, I managed to achieve what I wanted. Posting in case it helps anyone learning in future. ; process keyboard input of verbs or noun codes proc_input jsr t_clbuff ; clear kb buffer jsr clear_nv ; clear the current value from screen lda #0 sta TMP ; init our input count pi_plot ...
- Fri Oct 13, 2023 9:03 am
- Forum: Programming
- Topic: Keyboard Input in Assembly - advice sought
- Replies: 14
- Views: 6145
Re: Keyboard Input in Assembly - advice sought
Hey chysm - you did and I have used it as a basis for what I'm doing. Many thanks.
- Fri Oct 06, 2023 9:10 am
- Forum: Programming
- Topic: Keyboard Input in Assembly - advice sought
- Replies: 14
- Views: 6145
Re: Keyboard Input in Assembly - advice sought
Hey mike, Here's some pseudo pseudo code of what I am trying to achieve: When 'V' is pressed Loop: Move cursor to a specific column and row on screen Read a key Verify it is numeric If not numeric discard and jump to loop If numeric display the entered number at the cursor location Increment the cur...
- Fri Sep 29, 2023 9:43 am
- Forum: Programming
- Topic: Keyboard Input in Assembly - advice sought
- Replies: 14
- Views: 6145
Re: Keyboard Input in Assembly - advice sought
Hey Mike, I'm not working on this very often, it's a hobby project I revisit on Fridays after work (you'll be be pleased to know I'm not a programmer :D ) When I have time. I don't have a BASIC version as I'm using this project to learn Assembly language. The responses from the others in the thread ...
- Fri Sep 22, 2023 9:16 am
- Forum: Programming
- Topic: Keyboard Input in Assembly - advice sought
- Replies: 14
- Views: 6145
Re: Keyboard Input in Assembly - advice sought
ChatGPT, no way - I'm just learning and making mistakes, I don't need a machine to "do" that for me. :D "it doesn't work quite right" is not exactly helpful to describe what you might think is wrong with the routine. Ok, so I think I'm probably calling the wrong routines to get k...
- Fri Sep 15, 2023 9:16 am
- Forum: Programming
- Topic: Keyboard Input in Assembly - advice sought
- Replies: 14
- Views: 6145
Keyboard Input in Assembly - advice sought
Hi all, I'm still working on my Apollo DSKY on the 3k Vic 20 :D I'm trying to. Move the cursor to a specific row/col , get a 2 character input and check that it is made up of numbers. Here's my code - suffice to say it doesn't work quite right... verb_input jsr t_clbuff ; clear kb buffer lda #0 sta ...
- Tue Jun 20, 2023 8:57 am
- Forum: Programming
- Topic: Interrupt handling Tutorial
- Replies: 6
- Views: 2798
Re: Interrupt handling Tutorial
Thanks Mike, I'll take a look at that. I'm emulating a peripheral, that's why I wanted to explore this approach.
- Mon Jun 19, 2023 9:33 am
- Forum: Programming
- Topic: Interrupt handling Tutorial
- Replies: 6
- Views: 2798
Interrupt handling Tutorial
Hi all, Could anyone recommend a good tutorial for interrupt handling on the Vic? What I want to do is regularly check a memory location and then update the screen based on what I find, then carry on with normal processing. At a later point I will be wanting to check for keyboard input and processin...
- Sat Mar 11, 2023 3:30 am
- Forum: Programming
- Topic: Custom char issue in 6502
- Replies: 20
- Views: 4565
Re: Custom char issue in 6502
Thanks - it's working that way just fine, just trying to be efficient 

- Tue Mar 07, 2023 11:16 am
- Forum: Programming
- Topic: Custom char issue in 6502
- Replies: 20
- Views: 4565
Re: Custom char issue in 6502
So is there a short cut using the same EOR method to adding / subtracting 72? I have a char set with 144 characters, first 72 are normal video, final 72 are reversed and I need code to switch between them. I tried EOR and got the wrong answer. So I just wrote the longer version with adc/sbc. 24 EOR ...
- Sat Feb 25, 2023 7:33 am
- Forum: Programming
- Topic: Custom char issue in 6502
- Replies: 20
- Views: 4565
Re: Custom char issue in 6502
Worked a treat and my routine is working primo
Thanks for the help

- Sat Feb 25, 2023 2:42 am
- Forum: Programming
- Topic: Custom char issue in 6502
- Replies: 20
- Views: 4565
Re: Custom char issue in 6502
Thanks Chysn, you're right that is really elegant, reusing the same pointer for both purposes.