_________________
http://WilsonMinesCo.com/ lots of 6502 resources
The "second front page" is http://wilsonminesco.com/links.html .
What's an additional VIA among friends, anyhow?

I prefer CONFIG to be active low, personally. It'd make generating microcontroller interrupts easier for one, and secondly, things just seem to work better with active-low signals across a longish cable. Not sure why.

_________________
http://WilsonMinesCo.com/ lots of 6502 resources
The "second front page" is http://wilsonminesco.com/links.html .
What's an additional VIA among friends, anyhow?

Yes; I've always intended for CONFIG to be active low. I didn't use an overbar because you don't appear to use it for the SEL lines, and I was striving for consistency.

Inconsistent documentation conventions leads to things like, oh I dunno, Mars probes crashing into asteroids or otherwise going silent in the depths of space.

_________________
http://WilsonMinesCo.com/ lots of 6502 resources
The "second front page" is http://wilsonminesco.com/links.html .
What's an additional VIA among friends, anyhow?

uh...thanks...I think.


Believe it or don't I actually have an EE degree and not a CS degree. (I can hear the peanut gallery now: "That explains a lot about your software" ) But with hardware, I tend to have to draw a block diagram or schematic to explain (or understand) things. With software, code examples can be thought up and typed in or cut-and-pasted more quickly, so software can be more conducive to forum discussions.

Garth said...


Yes, it's true: This thread is a little much for my small mind, so I don't read everything in it. Sorry I missed your post about the SX's that I recommend.

The SX does not have an SPI port. What it has is pipelined operation rated up to 75 MHz, 1 MIPS per MHz. (They are overclockable). I am not sure what you meant about the SX having to access its parallel port or something to get to it's IO pins. Did I cross streams there? The SX has direct access to it's IO pins. There is still a DIP version available (among surface mount options).

With the wonderful speed you can bit-bang the dickens out of SPI or... pseudo-SPI or I2C or whatever. That's the wonderful thing about not having dedicated silicon purposed to a peripheral and having high-speed. At less then $3.00 a piece, even in one-offs, whether one wants to cry about how lousy one thinks the instruction set is or not, it can't be beat for cheap, custom serial protocol-ing. It's so cute and pipelined.

SX Microcontroller...will you be my valentine?

P.S. Here's the latest datasheet for the SX48 flavor: http://www.parallax.com/dl/docs/prod/datast/SX48BD-Data-v1.5.pdf

_________________
Thanks for playing.
-- Lord Steve

_________________
http://WilsonMinesCo.com/ lots of 6502 resources
The "second front page" is http://wilsonminesco.com/links.html .
What's an additional VIA among friends, anyhow?

I'm using an FPGA for my upcoming Kestrel, so "dedicated hardware" or "dedicated stack-based MISC I/O processor" or "IBM-style mainframe I/O processor" -- doesn't matter to me. I can hack hardware as easily as software.

However, this bus is intended to be used both with hobby SBCs that bit-bang everything (e.g., a Kestrel-1 with its one and only VIA chip) to custom hardware that supports 25Mbps throughputs. Only cabling affects top-end speed. The rest of the spec more or less remains the same.

Thus said Garth:
I, too, wasn't thinking about using the SX as the master, but as interface devices to sit in between the slave device and the bus, doing any translation necessary between the two. In other words the SX could add the "intelligence" needed to dumb devices so they can hang on your crazy bus.

Garth:
I have a feeling this is a silly question but...what other things?

_________________
Thanks for playing.
-- Lord Steve

Crazy bus?

All we did was package an existing bus (SPI) in a form that allows it to be useful as an external (versus internal) peripheral expansion bus.

I rather resent the insinuation that it's "crazy", because of the negative connotations it brings with it (namely, it's haphazardly designed, ill-specified, that sort of thing). While the auto-configuration protocol has not been fleshed out, the hardware specification IS being refined over time. Garth's experience is going to be the guinea pig test results on our current design iteration. Based on his feedback, since he'll be able to build an interface long before I ever will, we will then refine the interface specifications.

Like any collaborative project, the ultimate design will coalesce only over time. Give it a chance, please.

If I misinterpreted your intentions with the phrase, I apologize. But I have to admit, it sure read like trollbait.

_________________
http://WilsonMinesCo.com/ lots of 6502 resources
The "second front page" is http://wilsonminesco.com/links.html .
What's an additional VIA among friends, anyhow?

Sammy,

I wasn't being insulting so there's no need for hysterics. Good frickin grief, Samuel. Did you miss the point of my post only to concentrate on a presumed insult perhaps flung your way?

You're bus is "crazy" to me and I use the term lightly. There wasn't a shred of animosity in it. I don't have a clue how it works and I haven't read about it That's just how my personality formed the expression about it...a crazy ol' bus.

Maybe give some benefit of doubt when the majority of message's material is informative and benign when something potentially malignant pops into your view.

_________________
Thanks for playing.
-- Lord Steve

All I said is that I resent the insinuation that it was crazy, and that it rather read like trollbait. I wasn't being hysterical at all. The most hysterical thing I wrote was, and if you can call it hysterical, "Give it a chance."

I'll let your reaction to it speak for itself though.

A simple, "I didn't mean it that way, I meant it in the term of "that crazy ol' bus"" would have been sufficient and far more informative.

Kind of O.T. but:

I had forgotten about this but I've had gerber viewer software for a couple of years or more so I can now just put up a picture. I do my CAD in DOS on another computer so I couldn't even do a screenshot before. This is the ground plane layer of a little board I did a couple of years ago:



(It shows up on my monitor about three times actual size.) This one is cut into four sections. Three of them are joined at strategic points where switching power supply noise can be controlled and kept out of the audio.

I'll try to post a preliminary 65SIB spec soon. First draft is nearly done. I've been working on it a little at a time for the last week, since someone mentioned again that there really ought to be a place to get it concisely and not have to read this whole topic.

_________________
http://WilsonMinesCo.com/ lots of 6502 resources
The "second front page" is http://wilsonminesco.com/links.html .
What's an additional VIA among friends, anyhow?