SW1 (SWITCH ON <> SST) Strange behavior

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Marco Rey y Sander

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Nov 6, 2021, 7:09:09 AM11/6/21
to PAL 6502 computer
Hello PAL-1 friends,

last week I soldered the PAL-1 together. Now I test some functions and must determine that the switch between continuous and single step behaves with me exactly the other way around. I thought it doesn't matter how I turn the switch on or there was nothing obvious here that you should keep a certain installation direction. Result is now possibly also that the terminal behaves differently. If I press G I see the processing of a single command and must confirm the next step with G again. If I switch the SW1, then I can enter G in the terminal, must eliminate with Return and nothing more happens at the terminal. Does anyone have similar experiences?

tanks and best regards
Marco

Liu GN

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Nov 6, 2021, 9:39:11 AM11/6/21
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Hello Marco,

The SST mode needs set the NMI vector to 1C00 (17FA - 00, 17FB - 1C) first, then slide the SST switch to ON (to your left). After that, you can try press GO (on PAL-1 keypad) or G (on terminal) to single step your program.

When you execute your program in single step, you do need press GO/G for the next instruction to be executed.


Thanks,

Liu

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Hendrik-Jan Megens

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Nov 6, 2021, 10:14:52 AM11/6/21
to Liu GN, PAL 6502 computer
In fact I literally printed that lesson from page nine of the FBoK and stuck it to my PAL-1; I forgot this so many times....

20211106_150127.jpg

Neil Andretti

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Nov 6, 2021, 11:13:06 AM11/6/21
to PAL 6502 computer
Hahahaha.  I've seen something like this already  on the back of my mobile...
handy_rear.JPG

Marco Rey y Sander

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Nov 6, 2021, 11:28:49 AM11/6/21
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Hi, its clear to setup 17FA,17FB AND 17FE,17FF. I did...and do it again and again when I plug it in. 😊

My current problem is this: I have the EPROM board connected and can see the memory areas with the terminal. If I look for example at BANK 1 $B000, I get the following values: D8,A2,DD,9A,80,80... D8 = CLC, A2 = LDA, etc. So it seems to work, but if I press G at $B000 nothing happens. I would have expected the Woz monitor now. How can I check whether I am really addressing the correct "module"?

Hendrik-Jan Megens

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Nov 6, 2021, 11:34:08 AM11/6/21
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Hi Marco, did that behaviour you described earlier going away with setting the interrupt vector?

Regarding the ROM, what happens when you start from 0xA000?

Liu GN

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Nov 6, 2021, 11:40:11 AM11/6/21
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For the ROM card Bank 1 (upper bank), the value from $B000 will be these:

B000 D8
B001 A2
B002 FF

...

THE B002 IS IMPORTANT, seems your data is not correct.

Did you set the tweak pins? the A13 need to be A13# (close the upper two pins)


Thanks,

Liu

Liu GN

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Nov 6, 2021, 11:46:00 AM11/6/21
to Hendrik-Jan Megens, PAL 6502 computer

Hi Hendrik-Jan,

I think Nils' is more practical than yours ;) Just for kidding

Liu

Hendrik-Jan Megens

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Nov 6, 2021, 11:56:40 AM11/6/21
to Liu GN, PAL 6502 computer
Hi Liu, true! Nils' solution is pretty hard-core-happy-hacking-6502! 

Marco Rey y Sander

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Nov 6, 2021, 12:29:09 PM11/6/21
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My current setup. Something wrong?
Values in B000 (and follows) are: d8,a2,did,9a,80,80,00,00,29,b1
BE0DA44F-4617-467A-BE85-FE6D1AA679C6.jpeg


Marco Rey y Sander

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Nov 6, 2021, 12:29:34 PM11/6/21
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B7D3BC45-E05E-4894-826D-73B06D065C50.jpeg

Marco Rey y Sander

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Nov 6, 2021, 12:30:04 PM11/6/21
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53A1778B-3374-4859-8E31-6CE9EF28B396.jpeg

Neil Andretti

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Nov 6, 2021, 3:50:37 PM11/6/21
to PAL 6502 computer
looks odd.

bank1_b000.png
a shortage of one pin?

GN L

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Nov 9, 2021, 2:25:28 AM11/9/21
to PAL 6502 computer
From your very detailed pictures, I see you closed the MEMORY SELECTOR pin. When you using the ROM or RAM card, you need to open the pin at the right side of PAL-1 logo.

Marco Rey y Sander

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Nov 13, 2021, 7:53:38 AM11/13/21
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Hi, 

with me it always takes a while with the answer, because I somehow only get to my hobby on the weekend ;) I am now a bit further. Who can read is clearly at an advantage. The EPROM board works only with the RAM extension. Then also the Memory Selector (JP2) works. With me the display remained dark, since I had only the EBROM board active. Now I can start Basic, the eWoz etc. and really let off steam!!!

regards
Marco

Will Senn

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Apr 28, 2022, 10:45:51 AMApr 28
to PAL 6502 computer
IMG_3373.JPG

After about the 10th time that I wondered if things were working at all. I stooped to a sticky note.
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