How to power off the ZX81 correctly
How to power off the ZX81 correctly
Hi at all,
i ask a doubt i have;
how to power off correctly the ZX81?
From mains AC or cut down directly from the power jack?
Where is the most " soft" power off for the Power brick, and the microcomputer?
Thanks at all,
Matt
i ask a doubt i have;
how to power off correctly the ZX81?
From mains AC or cut down directly from the power jack?
Where is the most " soft" power off for the Power brick, and the microcomputer?
Thanks at all,
Matt
Re: How to power off the ZX81 correctly
I use to remove the jack 2-3 seconds… and i plug-in it again.
While this process, the RAM pack can move, and freeze the CPU !
Always put the rubber stick under the zx case, to avoid to shake the extension board while pressing a key or insert the jack.
While this process, the RAM pack can move, and freeze the CPU !
Always put the rubber stick under the zx case, to avoid to shake the extension board while pressing a key or insert the jack.
Xavier ...on the Facebook groupe : "Zx81 France"(fr)
Re: How to power off the ZX81 correctly
Thanks Xav;
Same procedure with power on?
Greetings,
Matt
Same procedure with power on?
Greetings,
Matt
- 1024MAK
- Posts: 5118
- Joined: Mon Sep 26, 2011 10:56 am
- Location: Looking forward to summer in Somerset, UK...
Re: How to power off the ZX81 correctly
It does not really matter. You can either disconnect the mains or the low voltage 3.5mm power jack plug.
To power up, again either method can be used. However, as Xav points out, when powering on by connecting the 3.5mm power jack plug, hold the socket firmly so that the ZX81 does not move. Otherwise if using a memory expansion (RAM pack) or other expansion, the vibration / movement may cause a wobble and result in a crash. Then you have to try again
Some members have connected a in-line switch (like used on table lamps) into the low voltage cable. Or use a ready made in-line switch (these are available with 2.1mm/5.5mm barrel connectors) and suitable 3.5mm to 2.1mm/5.5mm barrel adaptors.
Mark
ZX81 Variations
ZX81 Chip Pin-outs
ZX81 Video Transistor Buffer Amp
Standby alert
There are four lights!
Step up to red alert. Sir, are you absolutely sure? It does mean changing the bulb
Looking forward to summer later in the year.
ZX81 Chip Pin-outs
ZX81 Video Transistor Buffer Amp
Standby alert
There are four lights!
Step up to red alert. Sir, are you absolutely sure? It does mean changing the bulb
Looking forward to summer later in the year.
Re: How to power off the ZX81 correctly
Thanks Mak.
Now it is clear for me.
Matt
Now it is clear for me.
Matt
Re: How to power off the ZX81 correctly
I have a switch at the 230V line.
If a "not so good" power supply is used without load it can go quite high with the voltage. Then the "stress" to the Zeddy (and extensions) 5V circuit is higher than necessary.
Building up the transformer voltage with the Zeddy plugged in (having a load) these peaks in voltage are avoided. Powering down either way doesn't matter.
This experience comes from Spectrum internal RAM failings when switching the low voltage instead of high voltage. This precaution can't be wrong with a ZX81 as well.
Kind regards Paul
If a "not so good" power supply is used without load it can go quite high with the voltage. Then the "stress" to the Zeddy (and extensions) 5V circuit is higher than necessary.
Building up the transformer voltage with the Zeddy plugged in (having a load) these peaks in voltage are avoided. Powering down either way doesn't matter.
This experience comes from Spectrum internal RAM failings when switching the low voltage instead of high voltage. This precaution can't be wrong with a ZX81 as well.
Kind regards Paul
In theory, there is no difference between theory and practice. But, in practice, there is.
Re: How to power off the ZX81 correctly
Always this way PRINT "SHUTDOWN IN PROGRESS" - wait 5 seconds and pull the 3.5mm plug out.
Be sure to wait at least 5 seconds to get the heads of the ULA in park position.
Funny question by the way - you made my day.
Be sure to wait at least 5 seconds to get the heads of the ULA in park position.
Funny question by the way - you made my day.
- 1024MAK
- Posts: 5118
- Joined: Mon Sep 26, 2011 10:56 am
- Location: Looking forward to summer in Somerset, UK...
Re: How to power off the ZX81 correctly
Will you get a blue screen of death if you don’t follow this advice
Mark
ZX81 Variations
ZX81 Chip Pin-outs
ZX81 Video Transistor Buffer Amp
Standby alert
There are four lights!
Step up to red alert. Sir, are you absolutely sure? It does mean changing the bulb
Looking forward to summer later in the year.
ZX81 Chip Pin-outs
ZX81 Video Transistor Buffer Amp
Standby alert
There are four lights!
Step up to red alert. Sir, are you absolutely sure? It does mean changing the bulb
Looking forward to summer later in the year.
Re: How to power off the ZX81 correctly
I recommend to use the following shutdown program:
Then you can pull the plug ...
Siggi
Code: Select all
call FAST
HALT
Siggi
My ZX81 web-server: online since 2007, running since dec. 2020 using ZeddyNet hardware
http://zx81.ddns.net/ZxTeaM
http://zx81.ddns.net/ZxTeaM
Re: How to power off the ZX81 correctly
True…
Code: Select all
10 FAST
20 RAND USR 0
30 PRINT "SHUT THE POWER DOWN VERY QUICKLY..."
40 PRINT "TOO LATE IF THE K IS BACK"
50 PRINT "RETRY PLEASE"
Xavier ...on the Facebook groupe : "Zx81 France"(fr)