Search found 9 matches

by the dude of dudes
Tue Dec 18, 2007 10:34 pm
Forum: Hardware and Tech
Topic: How does a keyboard work
Replies: 9
Views: 4533

Okay, after some further investigation here's the low down on how a keyboard is read: -Between scans PORTA is set to $7F -At the start of a scan (scans occur at 60hz, meaning 60 times per second) PORTA is set to $00. If no key is down, PORTB will read $FF and the entire Scan routine is skipped. -Eac...
by the dude of dudes
Wed Dec 12, 2007 8:49 pm
Forum: Hardware and Tech
Topic: How does a keyboard work
Replies: 9
Views: 4533

The KeyScan routine actually sets ALL pins high except for the row/column (whatever you wish to call it) it wants to read, this pin stays low. Then it reads PORTB to read that row. All pins high on that port means no keys are pressed, a zero on any pin means that corresponding key is depressed. This...
by the dude of dudes
Wed Dec 12, 2007 12:17 am
Forum: Hardware and Tech
Topic: How does a keyboard work
Replies: 9
Views: 4533

The RESTORE key is connected to GND when pressed. I'm wondering why the +5v line is on the pinout on the mainboard. The key matrix is directly powered by the CIA/VIA, so the +5v seems unnecessary, right?
by the dude of dudes
Tue Dec 11, 2007 7:51 am
Forum: Hardware and Tech
Topic: How does a keyboard work
Replies: 9
Views: 4533

How does a keyboard work

I'm wondering about a C64 keyboard actually, but since the VIC uses the same keyboard I thought I'd ask here. Here is how I understand it, please tell me if I am correct or not. The VIA/CIA drives a pin connected to the keyboard matrix row high, and checks for a high signal on the port connected to ...
by the dude of dudes
Sat Jan 27, 2007 9:59 pm
Forum: General Topics
Topic: Anyone remember this Commodore scam?
Replies: 15
Views: 10846

Reminds me of the time we "Rebelled" with the school library computers. They had the C-64's locked up in a metal case, with only the keyboard and right hand side ports exposed. A 1702 monitor sat on top. They had a bank of 4 of these. Sometimes, between classes, we'd go in and play a few ...
by the dude of dudes
Mon Dec 25, 2006 1:06 pm
Forum: Hardware and Tech
Topic: Paddle problems with Vic20..
Replies: 25
Views: 6996

I was just going to ask if anyone has successfully programmed the 1351 to work with the VIC. I still want to believe it is possible... That would require telling the 6560/6561 to change the rate at which it resets the paddle capacitor. Unfortunately, this rate is hardware fixed at Phi2/512 or about...
by the dude of dudes
Sat Dec 16, 2006 10:06 pm
Forum: General Topics
Topic: Electronics and Moisture
Replies: 7
Views: 5286

Unless your radiator has a leak (ie. is dripping on the floor) it wont add to the humidity in the room. Hot air can hold more moisture than cold air, so the air near the rad may have a higher moisture content. A window near a rad crates a pocket of colder air which isnt able to hold as much moisture...
by the dude of dudes
Sun Nov 19, 2006 10:25 pm
Forum: Hardware and Tech
Topic: Mini Soldering Lesson
Replies: 16
Views: 4299

Excellent page, thanks. I follow those steps as best I can when I'm soldering, and I've had a reasonable amount of practice. However, my solder joints are always a dull grey, not shiny like the page says they should be. They work OK, but I'm sure I'm doing something wrong. Any recommendations? I'm ...
by the dude of dudes
Sat Apr 01, 2006 2:03 pm
Forum: General Topics
Topic: Use my Commodore online!
Replies: 2
Views: 1686

Use my Commodore online!

Hello all! I know this isn't actually VIC related, but I have a C64 online for all to use for the next day or so. Use Hyperterminal and goto 137.186.176.148 port 6400. You'll actually be using my 64 online. I believe this could actually be ported to the Vic as well, if there is any interest I will g...