I thought I had found a bug in the Verilog, but the problem was that I wasn't remembering how it actually worked
This very telling.
There is a reason I keep campaigning for observance of the KISS principle. Even in the face of some marginal loss of potential performance or flexibility.
If the designer of the gadget can't keep it all in his head how am I expected to?
Anyway, never mind that. That now makes the question, what was the confusing thing? Sounds like it needs a big prominent notice attaching to it in the documentation.
There is a reason I keep campaigning for observance of the KISS principle. Even in the face of some marginal loss of potential performance or flexibility.
If the designer of the gadget can't keep it all in his head how am I expected to?
Anyway, never mind that. That now makes the question, what was the confusing thing? Sounds like it needs a big prominent notice attaching to it in the documentation.
It had to do with adding $FF to the PTRX/PTRY value in order to pre-decrement it for RETX/RETY usage, before possibly inverting all 8 bits for the cases of RDAUXR/WRAUXR/CALLY/RETY. I had read this thread and was on heightened alert for some problem in that section. So, I was scrutinizing things, and supposed I had found the culprit: I needed a value of $FE, in addition, for the case of RETY. I was thinking that the inversion (address reversal) was going on inside a parenthesized section, not on the outside. I was totally missing that it worked fine in its simple form, and was wrongly supposing that it must need some extra condition inside the parentheses. Don't even ask why I thought $FE was needed - oh, I remember, I thought it would be inversed to $01, but my thinking was a little panicked and I was certain that there was some problem - never mind that I had already tested things and they were fine. I don't think there's need for more documentation in this section. I just need to not errantly insist that something is wrong, when maybe everything's fine. If you are convinced there's a problem, you're likely to identify SOME cause in trying to solve it. Such was the case.
It had to do with adding $FF to the PTRX/PTRY value in order to pre-decrement it for RETX/RETY usage, before possibly inverting all 8 bits for the cases of RDAUXR/WRAUXR/CALLY/RETY. I had read this thread and was on heightened alert for some problem in that section. So, I was scrutinizing things, and supposed I had found the culprit: I needed a value of $FE, in addition, for the case of RETY. I was thinking that the inversion (address reversal) was going on inside a parenthesized section, not on the outside. I was totally missing that it worked fine in its simple form, and was wrongly supposing that it must need some extra condition inside the parentheses. Don't even ask why I thought $FE was needed - oh, I remember, I thought it would be inversed to $01, but my thinking was a little panicked and I was certain that there was some problem - never mind that I had already tested things and they were fine. I don't think there's need for more documentation in this section. I just need to not errantly insist that something is wrong, when maybe everything's fine. If you are convinced there's a problem, you're likely to identify SOME cause in trying to solve it. Such was the case.
Silly post's like my one probably didn't help the situation.
I'll go sit on the naughty chair for a while!
Silly post's like my one probably didn't help the situation.
I'll go sit on the naughty chair for a while!
This is just the nature of the work, at times.
When I lived in Helsinki twenty years ago, I was working alone all night in my office room of the apartment and sleeping during the day hours. It was winter, which meant it was barely twilight for just a few hours a day (when I happened to be asleep). In all that darkness and cold outside, and being alone inside, it was like I was in a sensory-deprivation tank. As I worked in my office, I recounted this long, gross story some coffee fiend at Parallax had told me about the life cycle of the hook worm, which is an intestinal parasite. It was really disturbing to think about. Then, I started wondering if I could maybe have hookworms. In that state of isolation, I convinced myself that I had hookworms. If you amplify nothing enough, you get a signal. I could feel them inside me. I was calling back to the USA talking to people about what I ought to do about it. I eventually went to see a doctor in Helsinki and told him what I had. He asked me if I had been to Africa, or travelled anywhere. No. I insisted though, that he take some samples to determine if I had parasites. Turns out I was fine.
Comments
There is a reason I keep campaigning for observance of the KISS principle. Even in the face of some marginal loss of potential performance or flexibility.
If the designer of the gadget can't keep it all in his head how am I expected to?
Anyway, never mind that. That now makes the question, what was the confusing thing? Sounds like it needs a big prominent notice attaching to it in the documentation.
It had to do with adding $FF to the PTRX/PTRY value in order to pre-decrement it for RETX/RETY usage, before possibly inverting all 8 bits for the cases of RDAUXR/WRAUXR/CALLY/RETY. I had read this thread and was on heightened alert for some problem in that section. So, I was scrutinizing things, and supposed I had found the culprit: I needed a value of $FE, in addition, for the case of RETY. I was thinking that the inversion (address reversal) was going on inside a parenthesized section, not on the outside. I was totally missing that it worked fine in its simple form, and was wrongly supposing that it must need some extra condition inside the parentheses. Don't even ask why I thought $FE was needed - oh, I remember, I thought it would be inversed to $01, but my thinking was a little panicked and I was certain that there was some problem - never mind that I had already tested things and they were fine. I don't think there's need for more documentation in this section. I just need to not errantly insist that something is wrong, when maybe everything's fine. If you are convinced there's a problem, you're likely to identify SOME cause in trying to solve it. Such was the case.
Silly post's like my one probably didn't help the situation.
I'll go sit on the naughty chair for a while!
This is just the nature of the work, at times.
When I lived in Helsinki twenty years ago, I was working alone all night in my office room of the apartment and sleeping during the day hours. It was winter, which meant it was barely twilight for just a few hours a day (when I happened to be asleep). In all that darkness and cold outside, and being alone inside, it was like I was in a sensory-deprivation tank. As I worked in my office, I recounted this long, gross story some coffee fiend at Parallax had told me about the life cycle of the hook worm, which is an intestinal parasite. It was really disturbing to think about. Then, I started wondering if I could maybe have hookworms. In that state of isolation, I convinced myself that I had hookworms. If you amplify nothing enough, you get a signal. I could feel them inside me. I was calling back to the USA talking to people about what I ought to do about it. I eventually went to see a doctor in Helsinki and told him what I had. He asked me if I had been to Africa, or travelled anywhere. No. I insisted though, that he take some samples to determine if I had parasites. Turns out I was fine.