Make your VIC turn on faster

Modding and Technical Issues

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carlsson
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Make your VIC turn on faster

Post by carlsson »

From the Personal Electronics Translator column by Greg Yob, published in Creative Computing, August 1982:
If you already have a PET, you know that the machine is reset by flipping the power switch on and off, and that the PET returns to life about 1/2 second later. The VIC works the same way, but the return to life takes nearly two seconds, which seems quite a long time.

If you are experienced in working with PC boards, the cure is simple. Remove the 1 µf capacitor near the 6502 and replace it with a .22 or .33 µf capacitor instead. I used a small mylar capacitor to ignore the polarity of the leads required by electrolytics. Now my VIC comes to life almost immediately (back to 1/2 second). As this project involves opening the case and removing the PC board, be aware that the modification will void your warranty. If you can't answer this question, don't attempt the project: What is an NE555 and how is it used on the VIC?
I'm not sure if this is a good suggestion; I'd expect there was a good reason why the larger capacitor is used and a greater delay in start-up time. Anyone who wants to argue this mod?

The article continues discussing how to add RES and NMI buttons, to generate these signals externally. It says they are only useful to machine code programmers, but a RES reset button should be useful to many people.

The text briefly mentions a VIC colour enhancement that your local dealer should be aware of. He doesn't say exactly what he refers to, but further down in the text he discusses the RF modulator. It was disturbing the picture a lot, and the author found that placing it on top of an aluminium plate reduced the "herringbones" and resulted in better colours. He suggests putting the RF modulator in the frying pan should also work.
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eslapion
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Re: Make your VIC turn on faster

Post by eslapion »

carlsson wrote:I'm not sure if this is a good suggestion; I'd expect there was a good reason why the larger capacitor is used and a greater delay in start-up time. Anyone who wants to argue this mod?
This one is really simple. In newer VICs this capacitor is in fact nowhere near the 6502. In the schematics shown in the Programmer's reference guide, it is listed as C22. It is used as a delay timing device by the NE555 which generates the initial reset at power-up.

A 1uF capacitor is a less expensive part because it is a more standard value and sells in larger quantities. 0.1uF is also a very standard value but it does not allow long enough a delay to ensure everything is properly set up when the CPU starts working.

Values such as 0.22uF will give long enough a delay but they were more expensive back then. Using 0.22uF will divide by about 4.5 the duration of the power-up reset. A value of 0.33uF will divide that duration by 3.
Boray
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Post by Boray »

Btw, does the CR model take longer to startup?
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e5frog
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Post by e5frog »

Which cap is it in an early C64 then? One of mine takes about four seconds to startup...
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ruud
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Post by ruud »

e5frog wrote:Which cap is it in an early C64 then? One of mine takes about four seconds to startup...
That's not the cap but the routine checking the RAM. JiffyDOS and SpeedDOS start up up much faster due to another RAM checking routine (or more by the lack of it).

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e5frog
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Post by e5frog »

My other three C64:s takes one or two seconds to start into plain BASIC (one Swedish from 1983, a C64G and a C64C), any ideas why this one takes so long? The slow one is from 1984.
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nbla000
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Post by nbla000 »

OT: 4 seconds for a full working PC wow, my current "Win-PC" takes about 4 minutes to start :wink:

Joking apart, I really don't know why in 2009 we must wait also 30/40 seconds for a full working PC, for me it is inconceivable !
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Post by rhurst »

Blame that legacy BIOS from the early 1980s for those startup times.

But use of a PC's suspend or hibernate modes make for much faster "startup" times. Virtual machines, such as VMware using Windows and Xen guests on Linux, start nearly instantly because there is no BIOS penalty time, and they too can "suspend" and "resume" (even "migrate" a running session to another host). The LinuxBIOS project allows many mobos to startup in less than 2-seconds, too.

I find that it is people who need to change their habits regarding the complete shutdown of their PC, regardless if it is Linux, Windows, or OSX.
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