Search found 92 matches

by LoneWolf33
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...
by LoneWolf33
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...
by LoneWolf33
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...
by LoneWolf33
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.
by LoneWolf33
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...
by LoneWolf33
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...
by LoneWolf33
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.
by LoneWolf33
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: ...
by LoneWolf33
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...
by LoneWolf33
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 ...
by LoneWolf33
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...
by LoneWolf33
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...
by LoneWolf33
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...
by LoneWolf33
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...