Search found 1335 matches
- Fri Feb 09, 2024 12:23 pm
- Forum: Programming
- Topic: "Ultimate Expansion" - new firmware for FE3
- Replies: 59
- Views: 13421
Re: "Ultimate Expansion" - new firmware for FE3
The IRQ clock, i mean could be placed under the normal screen. And of course with an alarm set and alarm tone. Taking over the IRQ once you've left the FE3 menus would be tricky. If you enter BASIC it would work ok until you wanted to run a program. It certainly wouldn't behave well if you launch a...
- Sat Feb 03, 2024 8:43 am
- Forum: Emulation and Cross Development
- Topic: Keyboard Buffer and Ctrl/Shift/CBM etc
- Replies: 20
- Views: 2917
Re: Keyboard Buffer and Ctrl/Shift/CBM etc
Correct.SparkyNZ wrote: ↑Sat Feb 03, 2024 8:12 am Right, so this is the result of the CRNCH routine?
Code: Select all
89 20 31 30 00
Using the monitor in VICE is a good way of understanding how this all works.Probably pay me to step through that routine and dump that piece of memory as it goes
- Sat Feb 03, 2024 1:58 am
- Forum: Emulation and Cross Development
- Topic: Keyboard Buffer and Ctrl/Shift/CBM etc
- Replies: 20
- Views: 2917
Re: Keyboard Buffer and Ctrl/Shift/CBM etc
Is the BASIC Input Buffer already tokenised? It is tokenized by the BASIC main routine that processes program input MAIN JMP (IMAIN) ; do BASIC warm start ;***********************************************************************************; ; ; BASIC warm start, the warm start vector is initialised...
- Thu Feb 01, 2024 1:46 am
- Forum: Programming
- Topic: "Ultimate Expansion" - new firmware for FE3
- Replies: 59
- Views: 13421
Re: "Ultimate Expansion" - new firmware for FE3
I miss two thinks on the FE3. - a clock like Mikes IRQ clock - some old fashion screen saver Do you mean these to be available while in the FE3 menus (rather than the BASIC wedge)? For the clock I'll have a think if that would fit on a subset of menus but screen space is tight so that wouldn't real...
- Sun Jan 28, 2024 2:31 pm
- Forum: Programming
- Topic: Recommendations for VIC-20 assembly tutorial, tools
- Replies: 10
- Views: 1954
Re: Recommendations for VIC-20 assembly tutorial, tools
I'm new to assembly language, and I would like to learn it for the VIC-20. There's a range of books that could be of help, which one(s) that will work for you depends on your background, how much knowledge you already have of the hardware, etc. https://commodore.bombjack.org/generic/generic-books-p...
- Sun Jan 28, 2024 3:34 am
- Forum: Emulation and Cross Development
- Topic: Keyboard Buffer and Ctrl/Shift/CBM etc
- Replies: 20
- Views: 2917
Re: Keyboard Buffer and Ctrl/Shift/CBM etc
This initial test is to check if any key in the matrix is down. Remember this function is called from the interrupt handler, it's trying to avoid burning CPU cycles when there's no keyboard input. Setting the column to all zeros mean the read of the row will be the union of all keys that are down. Y...
- Sat Jan 27, 2024 3:41 am
- Forum: Emulation and Cross Development
- Topic: Keyboard Buffer and Ctrl/Shift/CBM etc
- Replies: 20
- Views: 2917
Re: Keyboard Buffer and Ctrl/Shift/CBM etc
Here's the matrix keymatrix.png So 'M' is column 4 (b4), row 'E' (b4). The KERNEL routine loops over each column setting each bit in turn to be 0 and then reading the row. Pressing a key causes the row/column combination to shorted. The 6522 pulls inputs high when unconnected so this results in the ...
- Wed Jan 03, 2024 11:52 am
- Forum: Programming
- Topic: Updated BASIC and KERNAL disassembly
- Replies: 31
- Views: 12393
Re: Updated BASIC and KERNAL disassembly
One can only think that indirect JMP in the SE code is a brainf*rt ... it really should have been JMP $A2C2 instead: Thanks for the confirmation. The way I work on these disassemblies is I note oddities when I notice them and then come back when I understand the code better. On a related note, I ha...
- Wed Jan 03, 2024 2:40 am
- Forum: Emulation and Cross Development
- Topic: Please help with overwritten *.d64 (split/OT from: Flappy Bird [...])
- Replies: 4
- Views: 3394
Re: Please help with overwritten *.d64 (split/OT from: Flappy Bird [...])
Oh no. This very bad. Flappy killed my floppy :( In Vice I had my working disk attached. Then I loaded Flappy and played it. Now I turn on Vice and the contents of my working disk is the one of Flappy bird. I was working on my text adventure. Lucky my I printed a listing (file vice.out) and lucky m...
- Wed Jan 03, 2024 2:17 am
- Forum: Hardware and Tech
- Topic: Vic 20 Rev D, low voltage across the board, black screen
- Replies: 16
- Views: 7801
Re: Vic 20 Rev D, low voltage across the board, black screen
Don't suppose you could tell me where on the PCB L3 is could you? I can not find it to save my life. Found L1, L2, and L4 I only have one CR VIC, looking at the PCB I can't see an L3 either. Here's a shot near the power switch vic20-cr-switch.jpg Tracing the circuit I make out the pins as the follo...
- Tue Jan 02, 2024 2:27 pm
- Forum: Hardware and Tech
- Topic: Vic 20 Rev D, low voltage across the board, black screen
- Replies: 16
- Views: 7801
Re: Vic 20 Rev D, low voltage across the board, black screen
[Getting better voltages from socket, but I dont know how to "hotwire" the switch to have it always on, for testing purposes, until I can get another switch. So there is no switch on the board. Any ideas, Thanks in Advance. We can ignore the 9V AC side for now, it's not required for the m...
- Sun Dec 31, 2023 12:30 pm
- Forum: Programming
- Topic: Filename Character Filter
- Replies: 5
- Views: 2387
- Sat Dec 30, 2023 1:41 am
- Forum: Programming
- Topic: New Keywords
- Replies: 8
- Views: 2521
Re: New Keywords
You might find the disassembly of the Super Expander useful to learn about this subject https://eden.mose.org.uk/gitweb/?p=rom-reverse.git;a=blob;f=src/vic-1211a-superexp.asm;hb=HEAD That uses a two step process when executing commands, first it handles arguments and then has another dispatcher that...
- Thu Dec 28, 2023 1:45 am
- Forum: Programming
- Topic: "Ultimate Expansion" - new firmware for FE3
- Replies: 59
- Views: 13421
Re: "Ultimate Expansion" - new firmware for FE3
diagnostics I get this: register.... ok vendor/dev.... 144/144 rom/xmode....error#1 ram-mode1....ok blk-protect....ok blk-disable....ok ram-mode2....ok fe3-512kb detected OK, I think this shows that the CPLD and RAM parts of the hardware are OK. The vendor/device are still bogus and the ROM mode te...
- Wed Dec 27, 2023 2:19 am
- Forum: Programming
- Topic: "Ultimate Expansion" - new firmware for FE3
- Replies: 59
- Views: 13421
Re: "Ultimate Expansion" - new firmware for FE3
I had been running a previous version of this firmware (Ultimate), and turned on my Vic-20 today and I get no menu etc, just a BASIC prompt. That doesn't sound good. I would think that would indicate the flash is either corrupt or not working at all. I want to upgrade to 1.7 so I have to use the fl...