Help identifying and connecting Commodore 64 Hardware

jumpinjackson

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Hello,

last summer I was doing a final clearing of my stuff from my old room in my mum's house and I almost cried when I found these in a box hidden well in the back of a closet.





I haven't seen these :Commodore: "fellows" for nearly 30 years... here the thing though: it's been 30 years, I have no memory what exactly these mods are and how to connect the C64 to the 1541 :double.
I can connect power and video but do not remember if the "Speedos" (as it was called in Italy, I assume it should be a Jiffy-DOS) needs just its own connector or also the Commodore serial cable.

Here are some pictures of the C64:










and the 1541








Any help is as usual very much appreciated :bowdown:

Thanks JJS
 
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What you have is called Speed DOS and uses a parallel connection, hence the extra user port connector. JiffyDOS only uses the regular serial cable and requires no hardware mods besides updated ROMs.
There is some info about Speed DOS here:
http://sta.c64.org/cbmpar.html

Basically, you connect the user port connector as well as the normal IEC cable and you should be good to go, provided everything still works after 30 years in hibernation. :)
If you haven't powered the C64 on yet, I would be very cautious about using the standard PSU without checking the output voltage first. It is not uncommon for the breadbin PSUs to go faulty and output ~12V on the 5V rail, thus killing lots of ICs in the 64 when you turn on the power. So before hooking anything to the PSU, check that 5V is indeed 5V.
 
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What you have is called Speed DOS and uses a parallel connection, hence the extra user port connector. JiffyDOS only uses the regular serial cable and requires no hardware mods besides updated ROMs.
There is some info about Speed DOS here:
http://sta.c64.org/cbmpar.html

Basically, you connect the user port connector as well as the normal IEC cable and you should be good to go, provided everything still works after 30 years in hibernation. :)
If you haven't powered the C64 on yet, I would be very cautious about using the standard PSU without checking the output voltage first. It is not uncommon for the breadbin PSUs to go faulty and output ~12V on the 5V rail, thus killing lots of ICs in the 64 when you turn on the power. So before hooking anything to the PSU, check that 5V is indeed 5V.

Many many thanks!!!(y)(y)

I should have some "me" time around Easter, I'll make sure to check the PSU and then give it a try.
A few more questions:

1. I'm thinking to move the cable hanging on the side of the 1541 and replace it with a more elegant port on the back of the disk drive. I would then need to modify the existing grey cable with a connector for the new port.

2. I would also like to build a cable to connect the 1541 to a PC

I had a look at the link you've sent but I got lost with all the cables descriptions. If I want to do the 2 above, would you know which cables I should build?

3. Is Speed DOS compatible with SD2IEC?

I need to get some disks Doh! :Doh:

Thanks again for your help.

JJS
 
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You need two cables between the C64 and the 1541. One is the standard IEC/serial cable (round plug) and the other is the Speed DOS/parallel cable. I think you could probably still use the 1541 like a normal 1541 if you only connect the IEC cable. It just wouldn't use the fast load functions from Speed DOS. You could replace the integrated parallel cable with a separate cable which plugs into a custom connector in the back of the disk drive. Which connector you want to use is up to you, but I think a D-Sub is not uncommon as it is easily available.

SD2IEC is not compatible with Speed DOS. It only has the IEC connector and does not emulate the 1541 as such, only the IEC protocol. It does support some fast loader protocols as well, for example Final Cartridge, so the SD2IEC and a FC3(+) is a useful combination.

If you go into the C64 world, I think you might as well end up looking at the 1541 Ultimate-II+ cartridge. It is a fantastic product and hard to live without once you have it. :)
It emulates disk drives, cartridges, printers, datasettes, stereo SID and has lots of other cool features:
http://www.1541ultimate.net/content/index.php?option=com_content&view=article&id=42
 
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You need two cables between the C64 and the 1541. One is the standard IEC/serial cable (round plug) and the other is the Speed DOS/parallel cable. I think you could probably still use the 1541 like a normal 1541 if you only connect the IEC cable. It just wouldn't use the fast load functions from Speed DOS. You could replace the integrated parallel cable with a separate cable which plugs into a custom connector in the back of the disk drive. Which connector you want to use is up to you, but I think a D-Sub is not uncommon as it is easily available.

SD2IEC is not compatible with Speed DOS. It only has the IEC connector and does not emulate the 1541 as such, only the IEC protocol. It does support some fast loader protocols as well, for example Final Cartridge, so the SD2IEC and a FC3(+) is a useful combination.

If you go into the C64 world, I think you might as well end up looking at the 1541 Ultimate-II+ cartridge. It is a fantastic product and hard to live without once you have it. :)
It emulates disk drives, cartridges, printers, datasettes, stereo SID and has lots of other cool features:
http://www.1541ultimate.net/content/index.php?option=com_content&view=article&id=42


Thanks again for all the tips, I had read about the 1541 ultimate but got ultimately ;) always been put off by its price.

I'll play around with my old jewel and see if it's still working.
 
Yes, it is not particularly cheap, but I've seen several examples where people over time buy this and that and end up paying just as much. First you get an SD2IEC, then you might want an FC3 for speed loader, then perhaps a Tapuino for tape stuff, and then you find out that you cannot run most demos with SD2IEC since they require a proper 1541 emulation. So it might be cheaper to just buy the full monty from the beginning. :)
 
What you have is called Speed DOS and uses a parallel connection, hence the extra user port connector. JiffyDOS only uses the regular serial cable and requires no hardware mods besides updated ROMs.
There is some info about Speed DOS here:
http://sta.c64.org/cbmpar.html

Basically, you connect the user port connector as well as the normal IEC cable and you should be good to go, provided everything still works after 30 years in hibernation. :)
If you haven't powered the C64 on yet, I would be very cautious about using the standard PSU without checking the output voltage first. It is not uncommon for the breadbin PSUs to go faulty and output ~12V on the 5V rail, thus killing lots of ICs in the 64 when you turn on the power. So before hooking anything to the PSU, check that 5V is indeed 5V.

Hi, tried the psu with a multi-meter before hooking it up to the C64 but no joy... I get - 0 from any of the pins.

Any suggestions?
 
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Check the fuse ? Make sure you are testing AC pins and DC pins with correct setting on your multimeter and make sure your probes are insulated.
 
What did you use as reference/ground? The shield?
It might also be dead, so you could check the fuse.
 
It is not uncommon for the breadbin PSUs to go faulty and output ~12V on the 5V rail

I think this is a fisherman's tale.

I am sure someone will correct me, but I don't know how 230vAC stepped down to 9vDC (measured mainly at 10.54vAC). Passed through a bridge rectifier, smoothed by a 4700uF electrolyte capacitor and send to a linear voltage rectifier can be amplified to more than the input voltage. That being said the RAM chips will die given a little more than the prescribed 5vDC.
 
It is not uncommon for the breadbin PSUs to go faulty and output ~12V on the 5V rail

I think this is a fisherman's tale.

I am sure someone will correct me, but I don't know how 230vAC stepped down to 9vDC (measured mainly at 10.54vAC). Passed through a bridge rectifier, smoothed by a 4700uF electrolyte capacitor and send to a linear voltage rectifier can be amplified to more than the input voltage.

I have measured approx 12V on the 5V line on a C64 PSU, and I'm not a fisherman..
If the output winding is rated to 9VAC, the peak voltage is 9V*sqrt(2) = 12.7V. If the PSUs then use a silicon bridge rectifier, the peak voltage is then ~11.3V. Since the transformer can often output several volts more in an unloaded condition, having 12V on the output of a shorted 7805 is very realistic..
 
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What did you use as reference/ground? The shield?
It might also be dead, so you could check the fuse.
Fuse tests and looks OK.
I'm using the connector's shield as ground.
Multimeter is set to measure DC 20V as in pic.

65fbbecad99593a7f8311533554880d3.jpg


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I am not 100% sure that the shield can always be relied on being connected to ground from the PSU, so you better check its continuity against the Gnd pins inside the connector:
2rw84mb.png
 
I am not 100% sure that the shield can always be relied on being connected to ground from the PSU, so you better check its continuity against the Gnd pins inside the connector:
View attachment 121013
Could I check it inside the psu?

1dc8aa9292ef004ab480295b61d02821.jpg



Also my connector only has 4 pins, I managed to measure -5v between the two below but can't really measure the other twos...

Capture1.JPG


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the pins that are wider apart are ac,the ones closer together is 5 volts dc

- - - Updated - - -

if your going to test this supply load it first with a car brake light on the dc side
 
the pins that are wider apart are ac,the ones closer together is 5 volts dc

- - - Updated - - -

if your going to test this supply load it first with a car brake light on the dc side

Ok, thanks! Measured 11v AC between the top ones (wider apart) and -5V DC between the bottom ones.
Am I good to go or do I risk frying the C64? :D
 
If you measured -5vDC then you have the probes the wrong way around.

You are ok with these voltages and can try
 
Yeah, sounds good to me. The 5VDC supply should be stable even without load, but the AC voltage will be too high without load and 11VAC as you see is normal.
 
Yeah, sounds good to me. The 5VDC supply should be stable even without load, but the AC voltage will be too high without load and 11VAC as you see is normal.
Thanks to both, but no joy :( :( the C64 won't power up.
I need to have a look at some YouTube servicing videos, hoping it's nothing too serious....

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