Sounds like you've either broken a couple of joints or joined some together with the reflow, very easy to do by accident with smd stuff.
Best grab a large magnifier or usb scope by the sounds of things.
Good luck.
1040 STF showing occasional rogue pixels
Re: 1040 STF showing occasional rogue pixels
If it ain't broke, test it to Destruction.
Re: 1040 STF showing occasional rogue pixels
Apparently, RAM access has fallen down to 50% of regular ST performance. On the upside, the rogue pixels don't show up anymore. But, I see the occasional flash in the bottom 20% of the screen in Metrocross. It's rather subtile, more like a few lines dim during a single frame. The dimmed area in the picture below is not what I am talking about btw
Re: 1040 STF showing occasional rogue pixels
I didn't do any SMD soldering, only refreshed legs on the bottom of the PCB. I've checked all of them with a magnifying glass, none appear to be joined or anything. I'm now reflowing anything that looks suspicious.Forgottenmyname wrote: ↑Sat Sep 29, 2018 11:48 am Sounds like you've either broken a couple of joints or joined some together with the reflow, very easy to do by accident with smd stuff.
Best grab a large magnifier or usb scope by the sounds of things.
Good luck.
Re: 1040 STF showing occasional rogue pixels
I saw another bad pixel at the bottom of the screen when running YAART.
So basically, we're now stuck with an ST that still has memory problems and now runs at only 50% memory speed. Yay
So basically, we're now stuck with an ST that still has memory problems and now runs at only 50% memory speed. Yay
Re: 1040 STF showing occasional rogue pixels
I don't understand how this thread is 53 posts long now, as far as I can tell all you needed to do was replace the faulty ram.
Re: 1040 STF showing occasional rogue pixels
Exxos pointed me to this thread. It is correct that YAART does not test the ca. 2.5 kB of screen memory where the status is displayed. It'd increase the program's complexity significantly if it were to test these last bytes of memory with the same coverage as the rest. Yet, I'll think about what I can do to improve YAART in that regard.
I've seen that Exxos pointed you to a program that (specifically?) tests the screen memory -- without any status output. Did that program find any errors?
I've seen that Exxos pointed you to a program that (specifically?) tests the screen memory -- without any status output. Did that program find any errors?
Re: 1040 STF showing occasional rogue pixels
Well, for one this has been a learning experience for me. Besides that, it's not economical for us to replace the RAM in this machine. Since I'm not capable to replace the j-leaded RAM chips myself (I don't have any SMT soldering experience) we'd have to send it to a repair shop. I could of course fit in an Exxo's solderless memory upgrade kit but that'll set us back for nearly the price of two STs.
Moreover, I'm not yet convinced that 'simply' replacing the RAM will fix the problem. Since I haven't been able to detect any memory problems using 4 different testing utilities, I'd suggest that something else might be going on. As a side node: my friend managed to spot a memory fault in YAART a month or so ago but since I got my hands on this machine, I haven't seen any faults as I mentioned.
Now that the machine seems to run at 50% ram access speed (according to GemBench), I'd first like to know if that could even be the result of faulty RAM or possibly something else in the machine. Running at this lower speed, most memory problems have disappeared but it renders the ST pretty useless due to the now much lower performance.
Re: 1040 STF showing occasional rogue pixels
Thanks for checking this out.czietz wrote: ↑Mon Oct 01, 2018 7:08 am Exxos pointed me to this thread. It is correct that YAART does not test the ca. 2.5 kB of screen memory where the status is displayed. It'd increase the program's complexity significantly if it were to test these last bytes of memory with the same coverage as the rest. Yet, I'll think about what I can do to improve YAART in that regard.
I was just thinking, isn't it an option to relocate the screen memory during the test or even randomly at the beginning of the test, as a transparent (ptagmatic) solution? Or simply cover the last 2.5 kb of the screen as well and clean up the rubbish before displaying the stats as an option? I'm sure you know best how to solve this though.
I ran the specific program and it didn't report any errors either.
Re: 1040 STF showing occasional rogue pixels
Maybe just allow the screen to fill with whatever patten its testing, and just pause the text output during that time, and just display the text when not testing screen memory ? We don't need the text to display 100% of the time really.. and testing screem mem is only a few seconds...czietz wrote: ↑Mon Oct 01, 2018 7:08 am Exxos pointed me to this thread. It is correct that YAART does not test the ca. 2.5 kB of screen memory where the status is displayed. It'd increase the program's complexity significantly if it were to test these last bytes of memory with the same coverage as the rest. Yet, I'll think about what I can do to improve YAART in that regard.
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viewtopic.php?f=17&t=1585 Have you done the Mandatory Fixes ?
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viewtopic.php?f=17&t=1585 Have you done the Mandatory Fixes ?
Just because a lot of people agree on something, doesn't make it a fact. ~exxos ~
People should find solutions to problems, not find problems with solutions.
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Re: 1040 STF showing occasional rogue pixels
It may not make a difference, but your reference machine is an STE with TOS 2.06 and Blitter enabled, it may be worth looking at the reference you're comparing against just to be doubly sure of your readings.sandord wrote: ↑Sat Sep 29, 2018 12:02 pm Apparently, RAM access has fallen down to 50% of regular ST performance. On the upside, the rogue pixels don't show up anymore. But, I see the occasional flash in the bottom 20% of the screen in Metrocross. It's rather subtile, more like a few lines dim during a single frame. The dimmed area in the picture below is not what I am talking about btw
IMG_20180929_125222.jpg
Collector of many retro things!
800XL and 65XE both with Ultimate1MB,VBXL/XE & PokeyMax, SIDE3, SDrive Max, 2x 1010 cassette, 2x 1050 one with Happy mod, 3x 2600 Jr, 7800 and Lynx II
Approx 20 STs, including a 520 STM, 520 STFMs, 3x Mega ST, MSTE & 2x 32 Mhz boosted STEs
Plus the rest, totalling around 50 machines including a QL, 3x BBC Model B, Electron, Spectrums, ZX81 etc...
800XL and 65XE both with Ultimate1MB,VBXL/XE & PokeyMax, SIDE3, SDrive Max, 2x 1010 cassette, 2x 1050 one with Happy mod, 3x 2600 Jr, 7800 and Lynx II
Approx 20 STs, including a 520 STM, 520 STFMs, 3x Mega ST, MSTE & 2x 32 Mhz boosted STEs
Plus the rest, totalling around 50 machines including a QL, 3x BBC Model B, Electron, Spectrums, ZX81 etc...