An address bus glitch during T ADS will not affect chip selects if they are fully qualified by VDA and VPA . There seems to be some sort of illogical resistance around here to that, despite WDC themselves advising to do so in the data sheet
That's interesting, does it mean the 65C816 will unassert ...

Hey folks, sorry for vanishing for a while and leaving this issue with no activity. Got frustrated and took a couple months off. Also got I finally got employed so I can spend money on hobbies again. The software engineer job market right now is absolutely brutal.

The good news is I *think* I have ...

Having sampled a number of 65C816s in POC V1.3 while the logic analyzer was hooked up—one of which was an older 0.8µ Sanyo-cored part, I can tell you tADS was consistently right around 12ns on five volts and at room temperature. Using 12ns for tADS , /RD or /WD in your unit should become valid no ...

I think the relative phases of things is going to be the clue - presumably you have at least two channels? Clock plus one other, and the other one working down a list: chip select, write enable, read not write, address line. Perhaps trigger on chip select? (Chip select of the RAM which is getting ...

Neither clock signal looks good. The clock without the damping resistors looks horrid, to be frank, which means the resistors were actually helping. Something is definitely not kosher; I think you have an abnormal loading problem somewhere, judging by the way the rise and fall noticeably slow as ...

I also poked around with my scope a bit. One thing I noticed so far is that the 100 ohm resistors on the clock lines (intended to suppress ringing) were distorting the clocks a bit too much. So, I bodged across the resistors, and the clocks look better now. A16 coming off of the '573 latch also ...

PS: a question for jmthompson. In the lead post you included some data dumps. During that experiment, did you have any code executing in Bank 1? Just checking. (It looks as if you simply filled Bank 1 with $55 and then left it alone.) From where did you have code executing?

All the code at the ...

I've been doing more investigation today and narrowed this down a bit. What actually seems to be happening is that frequent writes to RAM seems to corrupt bytes in that same range in bank|1. In other words, heavy writes to even banks corrupt the same page in the next bank, but writes to odd banks ...

Everything else about this system is 100% stable for the last 3 years. Are you saying the problem developed recently? If so, was there any circumstance that might've brought it on?

It is impossible to say 100% for sure, as until fairly recently the memory layout had the stack and DP in the $Exxx ...

This is on my JRC-1 system. 8 MHz, 2 x 1 MB RAM, 512 KB ROM (currently on a memsim emulator)...certain memory pages get corrupted in multiple banks.
I’m having a little trouble following the Verilog for the CPLD. What exactly is being qualified by VDA and VPA ? Also, what is the speed rating of ...

This is on my JRC-1 system. 8 MHz, 2 x 1 MB RAM, 512 KB ROM (currently on a memsim emulator)

Basically, I've got an issue where certain memory pages get corrupted in multiple banks.

1. The pages in question are for the same pages as used for the stack and direct page, just not in bank 0.
2. I can ...

Specifically the direct page. And not so much tracking DB as (1) not understanding DP not being at $0000 and (2) inability to have more than one such segment. Try specifying the run attribute with a start address of $0 for the DP segments that aren't located on the zero page.

Hey, that seems to ...

as65? Do you mean ca65, the assembler cc65 ships with?
Yeah, I always mix up the name...

Also what do you mean with the assembler only has "bare minimum" support for the 65816? if you do mean ca65 then the only thing I know it can't do by itself is keeping track of the direct page and data bank ...

as65? Do you mean ca65, the assembler cc65 ships with?
No; this is Andrew Jacobs' As65 assembler

Nah he is right, I typo'd in my post and said as65 when I meant ca65. My project is based entirely around the cc65 suite of tools. It's just that in my mind "ca65" always becomes "as65" for some ...

Checking now, it appears the "Orca" suite - assembler, pascal and C compilers were there, but not for some time. (And the C compiler is written in Pascal). Since these projects are on Github under a source available, but no commercial use basis, then maybe some enterprising person can un-apple them ...