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It was even more complicated than clock speed and clock cycles. If I recall correctly the 6502 was a 2 phase clock whereas the Z80 was single phase and static thus more easily implemented. In general the Z80's plethora of registers (in comparison) made programming at the assembly language level potentially more efficient, particularly because affordable external memory was relatively slow. Nevertheless the 6502's instruction set was more suited to some types of memory addressing; it all depended on what one was trying to achieve.


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But if you programmed at the assembly language level, the Z80 was a LOT nicer to use than a 6502. But on the other hand, the Apple ][ came with a built in assembly language monitor that made debugging easier (although that 256 byte limit on the stack for a 6502 was a real PITA).


And don't forget the registers, the Z80 wins hands down compared to the 2 lonely registers + accumulator on the 6502.
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General Chat / Re: usb to hdmi
« Last post by gxti on Today at 10:48:09 AM »
You won't be able to play HD video over a USB video adapter unless it's USB 3. And a laptop that doesn't have HDMI or DisplayPort out definitely does not have USB 3.

EDIT: unless those devices crush the crap out of the video stream. Maybe she's old enough that she won't notice.
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Beginners / Re: Regulatory question regarding maximum cable length
« Last post by indole on Today at 10:46:18 AM »
After more discussion with the electrical people, they clarified that it wasn't the length of the cable that is the problem but more or less it was never suppose to have a cable that is not hard-wired in.  Apparently the equipment was originally intended to be hard-wired but when it was brought to the lab, it had a switch added and a cable so it could be plugged in, which is apparently not against code but isn't the best way to do it.  The new proposed solution is to replace the the cable with BX cable and hard-wire it to the panel, which I'm more satisfied with.

Thanks for the replies!



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More videos from the YT channel

https://www.youtube.com/channel/UCN5wWSFjmIQEShpf8L_wfvw/videos

Looks pretty good to me, other than there is still a lot of work to be done.

As for the PnP software they are using something called OpenPnP with kicad support (still on pre alpha)

http://openpnp.org/
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Data Precision 938 and one Fluke 1900A sold! Thank you!
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But if you programmed at the assembly language level, the Z80 was a LOT nicer to use than a 6502. But on the other hand, the Apple ][ came with a built in assembly language monitor that made debugging easier (although that 256 byte limit on the stack for a 6502 was a real PITA).


Oh yes, I remember that, mine in fact did not boot to BASIC but straight into the monitor *. To get the BASIC prompt you had to type ctrl-B. To return to the monitor CALL -151. But apart from the cycles per instruction differences that you mention, I think the huge difference I saw in running speed was mainly due to the floating point BASIC that came built into the TRS80. The Apple was so much snappier probably due to its (Steve Woniak's) integer-only BASIC. It didn't last long though, later II Plus models ditched the integer BASIC entirely in favor of microsoft's FP BASIC.

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Test Equipment / Re: Spectrum Analyzer - Rigol DSA815
« Last post by ted572 on Today at 10:37:29 AM »
Does anyone know how to restore Lost TG Calibration Data, or the procedure for for TG Calibration?
This is the result of Error 470/471, Calibration Memory Lost.
Any thoughts or assistance would be greatly appreciated.

   Thank you in advance for any information.
how did you enter into this problem ??
please explain...tnx
K
I was trying to help someone with this issue; and in the Service/Maintenance Mode, Calibration, page 2/2, I selected 'Clr Int Cal' and expected to go to additional menu options.  But it did just what it said - it erased the Cal. Data.  So you can say that it was my own fault, but it almost seems like a setup trap.  So far easy to lose the Cal. Data, and apparently no way to restore, or do the Cal. Data procedure.  BTW others have lost Cal. Data without thinking they did this.  So we don't have the full story yet.  And Rigol told us how to get into the Service/Maintenance Mode to Calibrate the DSA's internal 10 MHz Frequency Standard.  So this magic button is nearby, just waiting for someone to press it. Ouch! 
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Microcontrollers & FPGA's / Re: ARM Toolchain General Discussion
« Last post by andersm on Today at 10:36:46 AM »
Did you find any useful resources for building your own toolchain? I'm mostly using the CMSIS documentation and some app notes by Miro Samek.

See eg. crosstool-NG. There's also a ton of different build scripts floating around.
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Test Equipment / Re: Some advice on purchasing a (local) oscilloscope
« Last post by marshallh on Today at 10:33:00 AM »
The 54600B has one of the best UIs and responsiveness of any digital scope ever made. They do the screen refresh in hardware, with a precursor to current Agilent's Megazoom technology.

The 100mhz scope will let you know if something is horribly wrong. If you want to do proper SI analysis you will need 1 ghz scope as a starter for digital stuff. But until you are more committed don't bother, just get the 100mhz
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