Okay, I picked up a fair load of Commodore stuff recently, and now that I've tested all of it, up it goes! I'm just going to list the items and what I'm asking for them; I might be willing to consider a lower offer if you're buying multiple items, and I can combine shipping if you buy more than one item. (NOTE: I'm also selling it over on AmiBay, so things will go to the first buyer on either thread.)

Hardware
* Commodore 1701 monitor (composite and chroma/luma video input) - $30
* "Breadbox" model C-64 - $30
* Commodore 64-C - $30
* Composite video cable - $5

NOTE: I only have one composite-and-audio video cable to spare. If you buy one of the 64s and not the cable, I'll throw in an RF modulator for TV hookup free of charge.

* 2 brown 1541 drives (pull-down door model) - $20/ea.
* Okimate 120 dot-matrix printer - $15
* Cardco G-Wiz Centronics->serial printer interface - $5

Cartridge software - $5 apiece
* Fastload (Epyx) SOLD
* Super Expander (Commodore) SOLD

* Music Composer (Commodore)
* Visible Solar System (Commodore)

* Centipede (Atari) SOLD
* Clowns (Commodore)
* Defender (Atari)
* Solar Fox (Commodore) SOLD

Disk games - $10 apiece
These games come in their original boxes, with the manuals. The disks were unfortunately stored in a garage and will poop iron oxide on your drive head, but I'm including working copies I made as well as the original disks. Box condition is generally good; there's some creasing along the seams, but for the most part everything looks fine.

* Alien Syndrome (Sega) SOLD
* Out Run (Sega) SOLD
* Spy Vs. Spy I & II (Avantage)
* Super Huey II (Cosmi)

For your consideration, here's a picture of the boxes:
FS: A bunch of C-64 stuff...

So I acquired a flat 128 today and brought it home to try it out. Sadly, it doesn't work at the moment. No VIC, no VDC, no audio, no serial, nothing. After a little TLC and reseating of chips, it got to the point where it flashes the screen white when I turn the power on or off, but I've made no further progress.

I do have a handful of chips from other dead Commodores, so I can try replacing parts to see if it helps, but from the troubleshooting guide on zimmers.net it looked like the only (socketed) chip that would cause this kind of total failure would be the 8701 clock generator. I replaced that to no effect.

I'm not desperate to repair this thing; I have my own 128 that works just fine, and I was just going to sell this one. Still, I hate to write off a good computer if there's a simple way to fix it. So if anyone has any ideas on getting this thing working, I'd like to hear them. If I can't get it working, I'll probably sell it for parts, if anyone wants it.

The behaviors displayed, for reference:

• On power-on or power-off, the VIC screen flashes white, then phosphor-fades down to black. There is no other VIC output.
  
• There is no VDC output at all.
  
• Some sort of serial-bus reset signal gets sent out on power-on (it makes any attached drives do their reset move-to-track-0 bit.) However, it doesn't do anything else with the disk drives, even with a 128-bootable disk like CP/M inserted, so I think this is probably just a reflex action.
  
• Typing in BASIC commands blind does nothing I can discern; I've tried both disk access and sound functions with no result. Whether this means the keyboard isn't working or BASIC isn't working, I don't know.
  

I've tried this with both the power supply it came with and the power supply from my own 128; there is no change in behavior.

Any thoughts?

Is there any multicolor character editor for Windows that is neither .NET-based nor completely retarded? Seems like even the Covert Bitops (usually a paragon of good editor design) have produced some kind of idiot software that decides whether you're editing multicolor or hi-res characters based on the friggin' foreground color? And doesn't even let you select from all 16 colors for the foreground? Gah. I'm this close to just giving up and writing one myself, but I'd love to know that there's one person out there sane enough to have written a decent char editor...

Okay, this has been bugging me for a while. Is it possible to access the RAM that's underneath the character ROM and register area at $D000-DFFF? Mapping The Commodore 64 hints that it is possible, but doesn't say exactly how to do it, and the only control I can see for this area is the I/O-ROM select in register $01. It's not vitally important, but it would be nice if this area were available for use. Anybody know the answer?

Quick question: if I change the screen-map address in the middle of a frame, will the scanlines rendered after the switch start from the top of the new map, or the "correct" position in the new map?

Here's a question. I know that, when the 128 runs in 2MHz mode, it clock-stretches most I/O accesses to 1MHz. Does this include the REC registers for a 1700 or 1750 REU? And, more importantly, does this extend to the DMA transfers to and from an REU?

Is there a clear, concise memory map for the 128's Z80 mode? The one in the 128 Programmer's Reference Guide is just confusing. In particular, where does any Z80 ROM appear, and what's contained in that ROM?

A while back I tried building an X1541 cable with no success. Either I screwed it up, or my PC has one of the many, many shoddy parallel port implementations in the PC world...anyway, until I get that figured out, I was just wondering if anybody would be interested in writing a couple .d64s to physical disks for me. Specifically, I'd like the boot disk and blank template disk for the C-64 port of DOS/65, a sort of CP/M-inspired operating system for 6502-based computers.

I'd be willing to cover shipping, plus a little something for the disks and the time, so if anybody's interested, I'd appreciate it if you'd drop me a line!

Okay, so I want to build myself an XM1541 cable to make life easier. But that requires four 1N5819 or BAT85 diodes, which my local Radio Shack doesn't have. And from what I can find, it's difficult to buy them online in small quantities without getting shafted on shipping costs. So what I'm wondering is, what is the difference between these and the diodes Radio Shack does have? The purpose is just to prevent current from flowing one way, right? So, theoretically, any old diode should work. Is it a question of how much current they can block? If so, what tolerances should I look for on the other kinds?

At the request of someone on comp.sys.cbm and upon my own realization that there isn't much good VDC documentation out there, I aim to write a document that clearly explains how to use the VDC, since most of the existing documentation is heavily technical in nature. I've tried to explain things clearly, using my best approximation of the cheerily informal style featured in all those great '80s home-computer magazines (but especially Compute.) This is an early version, submitted for your perusal. Please tell me if I'm explaining things clearly enough.

Here is the document: http://john.seikdel.net/vdcmadeeasy01.htm

What I've got:
* Basic VDC register access, using the WRITEREG routine
* Documentation on text mode

What I need to do:
* Everything else, but especially bitmap graphics (coming next)

What I need:
* I need to either figure out how all the different screen-resizing registers work or have someone explain them to me.

Questions? Comments? Smart remarks?

Okay, I've been reading through the VDC documentation in Mapping The Commodore 128, and man is it complicated. I think I've got most of it figured out, but I still have a couple questions:

• As I understand it, the VDC, by default, operates in non-interlaced mode, with a character height of eight pixels, so it's running in 640x200, rather like CGA mode 2. But this means that the pixels are vertically stretched, or rather horizontally compressed, and the only way to get normal, square pixels (or rather, to appear to have them) is to turn on interlaced sync mode. Am I understanding this correctly?
• Speaking of interlaced, plain interlaced mode (mode 1) seems to function exactly like non-interlaced mode, only with the annoying jitter. Is there some hidden and surprising function of this that I've missed, or is it just utterly useless?
• I understand about setting the register number and waiting until the VDC is ready before writing to a register, but what about the memory-write register ($1F?) Is it possible to write the register-select value, wait for the ready signal, and then write a stream of values? In other words, could the REU potentially be used to transfer data to the VDC quickly?

Okay, I've been reading through the VDC documentation in Mapping The Commodore 128, and man is it complicated. As I understand it, the VDC, by default, operates in non-interlaced mode, with a character height of eight pixels, but the pixels are vertically stretched, or rather horizontally compressed. And the only way to get normal, square pixels (or rather, to appear to have them) is to turn on interlaced mode? Am I understanding this correctly?

I'm working on a little project of mine for C= 128 80-column mode, and I'd kind of like to do a version for C= 64 as well. But it absolutely requires 80 columns with individual color addressing, so you can't use the old half-character trick to fake 80 columns. So I'd like to at least support 64s with one of the actual 80-column cartridges out there, but since I don't have any of them, I'd like to pick the brains of anybody who's used them as to how they work. My main criteria are that the device provides 80x25 text mode with either a customizable character set or a Code Page 437-based character set built in, and individually-addressable color settings; bonus points if the background color is also individually addressable.

I have an SFX Sound Expander cartridge for my 128, but I also have a 1750 REU. I'd like to use them both, which should work fine as the Sound Expander has a pass-through, except that the Sound Expander's registers for the stupid piano attachment conflict with the REU registers. I've been informed that one of the jumpers on the 1750 can be cut and a switch installed to change the REU register base address, but I have a couple questions.

First, I've been told that one cuts jumper J2 to do this, but Googling around it seems that one's actually related to REU size. Which jumper is the one I need to cut, and where is it on the board?

Second, what is the new address for the REU registers?

Third, is there a way to modify the Sound Expander to just remove the piano registers?

Thanks!