Search found 92 matches
- Wed Apr 15, 2015 11:44 pm
- Forum: Commodore 8 Bit Programming
- Topic: Maximum RS232 speed on C64 user port
- Replies: 7
- Views: 26418
Re: Maximum RS232 speed on C64 user port
Update: I've performed some tests in regard of serial line speed, and it seems the transfer speed can't be increased above 2400bps, when trying it from Basic. The "mark" pulses on the oscilloscope are not getting thinner using the same time base, despite the higher speed setting in the tra...
- Sun Apr 05, 2015 5:06 am
- Forum: Commodore 8 Bit Programming
- Topic: Maximum RS232 speed on C64 user port
- Replies: 7
- Views: 26418
Maximum RS232 speed on C64 user port
Hi All, I've did some research recently, and found that the control register assigned to the RS232 communications would allow 19200 bps serial transfer speed setting. The contents of the control register can be set with either OPEN or POKE commands. The control register is located at decimal address...
- Thu Jan 15, 2015 11:23 pm
- Forum: Commodore Discussion
- Topic: 1351 mouse issue
- Replies: 11
- Views: 20294
Re: 1351 mouse issue
Hi Celestine, And welcome to the forum ! Well, I haven't tried to update the driver, because I wanted to handle mouse events by myself, inside of my program(s). I have checked the SID registers directly, where the X and Y coordinates should be present, and there's no change in the values during mous...
- Wed Nov 19, 2014 8:02 am
- Forum: Commodore Discussion
- Topic: 1351 mouse issue
- Replies: 11
- Views: 20294
Re: 1351 mouse issue
Well, yes it seems... (I bought it as a 1351).
I tried it with an other C64 with the same keyboard blocking result.
Finally I've opened up the mouse and instead of the 20pin MOS5717,
I found a 14pin BA10339 quad comparator. So it's not a 1351.
I tried it with an other C64 with the same keyboard blocking result.
Finally I've opened up the mouse and instead of the 20pin MOS5717,
I found a 14pin BA10339 quad comparator. So it's not a 1351.
- Mon Nov 17, 2014 11:37 pm
- Forum: Commodore Discussion
- Topic: 1351 mouse issue
- Replies: 11
- Views: 20294
Re: 1351 mouse issue
Hi, Thanks for the response. Yes, by default port #1 is selected as POTX and POTY signal source, but it can be switched to port #2 as well through the 4066 switch. Since the POTX and POTY registers showing constant 255 readings, I think the mouse inputs from the joystick ports are not reaching the S...
- Mon Nov 17, 2014 9:53 am
- Forum: Commodore Discussion
- Topic: 1351 mouse issue
- Replies: 11
- Views: 20294
1351 mouse issue
Hi Guys, Recently I've found the user manual of the 1351 mouse in the manuals section of this site. The manual contains a machine language program with a Basic loader, which works fine under Vice emulator, when "Grab mouse events" option is enabled. I've decided to try the program on a rea...
- Tue Oct 07, 2014 6:13 am
- Forum: Commodore Discussion
- Topic: 1541 issue
- Replies: 15
- Views: 29157
Re: 1541 issue
Update: the case treatment is finished. I plan to order a new warranty label,
in order to cover the spot where the original sticker was before.
in order to cover the spot where the original sticker was before.
- Mon Sep 29, 2014 12:19 pm
- Forum: Commodore 8 Bit Programming
- Topic: Designing an Interface for the User Port on the PET 4016
- Replies: 1
- Views: 15348
Re: Designing an Interface for the User Port on the PET 4016
Hi,
I hope You might find the following link useful:
http://www.classiccmp.org/cini/pdf/kilo ... 379%29.pdf
I hope You might find the following link useful:
http://www.classiccmp.org/cini/pdf/kilo ... 379%29.pdf
- Tue Sep 16, 2014 10:01 am
- Forum: Commodore Discussion
- Topic: 1541 issue
- Replies: 15
- Views: 29157
Re: 1541 issue
Update: the drive is working now. I've made an X1541 cable and transferred a drive check program to a disk. Meanwhile I've managed to find out the answers to most my questions: - I've checked the head resistances and they're normal, no short circuits - Regarding the voltage output of the read head: ...
- Sun Aug 24, 2014 12:17 pm
- Forum: Commodore Discussion
- Topic: 1541 issue
- Replies: 15
- Views: 29157
Another 1541 issue
Hi All, I've bought a 1541-II drive recently, which is not willing to read and write (format) disks. The drive powers up normally, without blinking fault codes on the front panel LED. When trying to load the catalog the disk spins up, the R/W head moves to nearly the middle of the tracks (probably t...
- Sun May 25, 2014 4:34 am
- Forum: Commodore Discussion
- Topic: rgbi to vga
- Replies: 3
- Views: 7586
Re: rgbi to vga
Hi, ...og velkommen til forumet. Theoretically the 9pin RGBI output of the C128 can be rewired to a 15 pin SVGA connector without using a converter, but the "low" 15.525kHz line frequency won't be tolerated by some monitors, resulting an "Out of range" or similar message. Anyway ...
- Sat May 10, 2014 1:40 pm
- Forum: Commodore Discussion
- Topic: EPROM Programming
- Replies: 1
- Views: 4815
Re: EPROM Programming
Hi, I'm not really a VIC20 expert, but I'm pretty sure the about that 2764A (8kbyte) and Motorola 68766 EPROMs were used in VIC20 cartridges in the old days. Theoretically the 2768A EPROM is supported by Willem programmer. Both mentioned EPROMs can be erased by exposuring the chip surface to short w...
- Wed Apr 16, 2014 11:58 pm
- Forum: Commodore Discussion
- Topic: Two sick 64's
- Replies: 13
- Views: 20902
Re: Two sick 64's
YOu can look at the Memory but that will not necessarily tell you if it is incorrect, unless you fill a segment with 256 bytes of zero's then read it back and see if it is difference then the zero's you loaded into it... SO you could take that approach.. This is what the previously linked RAM teste...
- Sat Apr 12, 2014 1:43 am
- Forum: Commodore Discussion
- Topic: Two sick 64's
- Replies: 13
- Views: 20902
Re: Two sick 64's
I've compiled back the machine language program from the data lines,
and it seems this program scans only a small 256 byte RAM area (from $A000 to $A0FF).
So the "0" result confirms the correct operation of this small RAM portion only...
and it seems this program scans only a small 256 byte RAM area (from $A000 to $A0FF).
So the "0" result confirms the correct operation of this small RAM portion only...
- Fri Apr 11, 2014 12:03 pm
- Forum: Commodore Discussion
- Topic: Two sick 64's
- Replies: 13
- Views: 20902
Re: Two sick 64's
SCART is also known as EIA Multiport in U.S. that may sounds more familiar. Most of the TVs are equipped with this type A/V connector. The C64 DIN to SCART / EIA Multiport cable looks like this: http://www.ebay.com/itm/Commodore-64-C64-128-VIC20-AV-SCART-lead-TV-cable-High-Quality-cord-NEW-/11122599...