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General Category => Technical Support => Topic started by: ukmarkh on 00:55, 15 February 16

Title: Does anyone have more information on 6 MHz CPC?
Post by: ukmarkh on 00:55, 15 February 16
I would really like to do this for my CPC, I have quite a few spare, so not scared in the slightest.


Is it possible? How big a deal is it? Do games actually run any faster i.e. Chase HQ, Outrun, Altered Beast?


If anyone has done this, would it be possible to produce a guide, show the rest of us?


Thanks in advance
Title: Re: Does anyone have more information on 6 MHz CPC?
Post by: ||C|-|E|| on 02:04, 15 February 16
You have the basics explained in the Wiki :)

6 MHz CPC - CPCWiki (http://www.cpcwiki.eu/index.php/6_MHz_CPC)
Title: Re: Does anyone have more information on 6 MHz CPC?
Post by: TFM on 04:06, 15 February 16
I did make a 6 MHz CPC a long time ago, it's super easy and the results are awesome. Even converted half a dozen of games for it. Now they are super smooth! It's just awesome!  :)
Title: Re: Does anyone have more information on 6 MHz CPC?
Post by: ZbyniuR on 19:13, 15 February 16
What kind monitor you have, and how FDD work with such speed?
Title: Re: Does anyone have more information on 6 MHz CPC?
Post by: TFM on 19:39, 15 February 16
Well, I used the regular CTM644, but I did change some CRTC register values. Basically you increase the 'Horizontal characters in total' by 50%. Then you get 50 Hz again. Now, you can blow up the screen and use 32 KB V-RAM. Mode 0 can be used (f.e.) with the usual 16 colors but with 50% higher resolution. I used 32 * 32 MODE 0 f.e. GFX can be so beautiful in such a MODE 0, because the pixel are getting close to be square instead of long bricks, ehm, you know what i mean... they are pushed together in X, so look way better.


The floppy works with with that speed, which is actually 50% higher. I converted games to a Data format which runs 50% more quick. On 3" disc the sectors are squeezed too, because the FDC is 50% faster. So you can store about 300 KB on one disc side using 15 sectors of 512 bytes, or even better 8 sectors of 1024 bytes, which gives a format of 320 KB (318 KB free). The 3" discs don't have a problem and work well, I still have one or two of them and they retain data since over 15 years. However I can't tell much about 3.5" discs and drives, simply because I didn't make a long array of tests. I created an format of 1.3 MB capacity and one of 1.2 MB, both worked.

Title: Re: Does anyone have more information on 6 MHz CPC?
Post by: ukmarkh on 23:05, 15 February 16
You have the basics explained in the Wiki :)

6 MHz CPC - CPCWiki (http://www.cpcwiki.eu/index.php/6_MHz_CPC)


It's more of a "Look what you can do" on that page, doesn't show in detail, needs an in depth guide on 'how to do it'.
Title: Re: Does anyone have more information on 6 MHz CPC?
Post by: TFM on 00:34, 16 February 16
The Wiki article tells all details needed, just exchange the crystal or add a 2nd one.  :)
Title: Re: Does anyone have more information on 6 MHz CPC?
Post by: PulkoMandy on 08:17, 16 February 16
Yes it's really that simple:
1) Remove 16 MHz crystal from motherboard
2) Insert 24MHz crystal
3) Profit!!!


It is possible to add a switch to select between the two crystals, you need a switch with two lanes and two positions (DSDT). Try to keep the wires short in that case.


Some warnings:
- You need to adjust CRTC values manually. There is no adjusted system ROM available (as far as I know?)
- Your floppy disks will be completely unreadable by any other machine. If you could reach 8MHz, they would be HD disks, but the electronics in the CPC won't work at such high speed. This creates a challenge in transferring data. Maybe tape can be used with the correct "speed write" settings?
Title: Re: Does anyone have more information on 6 MHz CPC?
Post by: Munchausen on 08:41, 16 February 16
It is possible to add a switch to select between the two crystals, you need a switch with two lanes and two positions (DSDT).

Typo? DPDT I think
Title: Re: Does anyone have more information on 6 MHz CPC?
Post by: ukmarkh on 13:24, 16 February 16
The Wiki article tells all details needed, but not how to solder or how to use a screwdriver.  :picard:


Title: Re: Does anyone have more information on 6 MHz CPC?
Post by: ukmarkh on 13:25, 16 February 16
Yes it's really that simple:
1) Remove 16 MHz crystal from motherboard
2) Insert 24MHz crystal
3) Profit!!!


It is possible to add a switch to select between the two crystals, you need a switch with two lanes and two positions (DSDT). Try to keep the wires short in that case.


Some warnings:
- You need to adjust CRTC values manually. There is no adjusted system ROM available (as far as I know?)
- Your floppy disks will be completely unreadable by any other machine. If you could reach 8MHz, they would be HD disks, but the electronics in the CPC won't work at such high speed. This creates a challenge in transferring data. Maybe tape can be used with the correct "speed write" settings?


Thank you for this extra information. A gentleman beyond reproach!
Title: Re: Does anyone have more information on 6 MHz CPC?
Post by: gerald on 13:42, 16 February 16
The Wiki article tells all details needed, but not how to solder or how to use a screwdriver.  :picard:
Quote
  • Some CPCs (manufactured with fast DRAMs) show a increase of speed by 50% (verified with at least one CPC6128 produced 1987).
  • In case of the older DRAM type the speed improvement is only 16.7%.This has been tested with this simple program :
Who made these statements ?
DRAM speed is dictated by the GA, so the 16/24MHz.
Either the DRAM support beeing accessed at such speed, or it does not support it and return garbage.
The CPC cannot adapt its memory access speed to the speed grade of the DRAM.
Title: Re: Does anyone have more information on 6 MHz CPC?
Post by: TFM on 18:49, 16 February 16
Yes it's really that simple:
1) Remove 16 MHz crystal from motherboard
2) Insert 24MHz crystal
3) Profit!!!

Well, I just added the 2nd crystal on the first one, so I can switch between them. (And a switch of course). Works nice :)

EDIT: You told all that, I should read more careful before posting!  ;D  But hey, I just worked 2 hours on the microscope, see too much dancing bubbles instead of letters now.  :picard:


The big advantage of having a "switch" solution is that you can copy files in the RAM disc (need constant power supply of battery, f.e. X-MEM with own PSU or Inicron RAM-expansion), then you can switch the CPC off, activate 6 MHz, then switch the CPC on, then copy your files to the disc.
And - schwupps - you have software on disc running with 6 MHz! The X-MEM also allows to use a new lower ROM, so you can adjust the CRTC values to your desire.
However, I did not yet test the X-MEM with the 6 MHz CPC. What I did is to test lots of older RAM and ROM expansions back in the day. So, some are 6 MHz compatible, some are not quick enough. You have to check this our. Maybe we can compile a list of compatible hardware?  :)


Who made these statements ?

Not me, my 6 MHz CPC does _everything_ 50% more quick. Even the sound. Speedup in games was 50% too. Of course if you change the CRTC values and a program waits to the Frame-Fly-Back then it will have impact. I guess you see where I'm driving at? Where they "influenced" their speed test?  ;) :)
Title: Re: Does anyone have more information on 6 MHz CPC?
Post by: gerald on 19:17, 16 February 16
Not me, my 6 MHz CPC does _everything_ 50% more quick. Even the sound. Speedup in games was 50% too. Of course if you change the CRTC values and a program waits to the Frame-Fly-Back then it will have impact. I guess you see where I'm driving at? Where they "influenced" their speed test?  ;) :)
Title: Re: Does anyone have more information on 6 MHz CPC?
Post by: TFM on 19:22, 16 February 16
No, try this....


Difference between revisions of "6 MHz CPC" - CPCWiki (http://www.cpcwiki.eu/index.php?title=6_MHz_CPC&type=revision&diff=68326&oldid=66964)

Title: Re: Does anyone have more information on 6 MHz CPC?
Post by: gerald on 19:36, 16 February 16
No, try this....


Difference between revisions of "6 MHz CPC" - CPCWiki (http://www.cpcwiki.eu/index.php?title=6_MHz_CPC&type=revision&diff=68326&oldid=66964)
No trace of :
Code: [Select]
Some CPCs (manufactured with fast DRAMs) show a increase of speed by 50% (verified with at least one CPC6128 produced 1987) until the last revision ....


Where you're wrong is by stating that Some CPCs (manufactured with fast DRAMs) show a increase speed by 50%.

All CPC are made equal  from the DRAM point of view, and if you where a bit more literate on HW, you would have been able to understand that.Be the visible speed increase 16 or 50% or any %, this speed is not tailored by the DRAM speed, nor the date of production. I have no idea of the real speed increase, but saying that some CPC will have different speed boost than other is just false.

In research domain, when you find a result that is in contradiction with the other scientist on the same experiment, your first task is to clarify that them and found who is wrong, not to publish your result and say on SOME blablabla ...

Title: Re: Does anyone have more information on 6 MHz CPC?
Post by: ukmarkh on 19:40, 16 February 16
If someone could produce a video guide on how to do this and install a switch, I believe it would really help the CPC community.


Amstrad CPC Dummies guide!  :laugh: 
Title: Re: Does anyone have more information on 6 MHz CPC?
Post by: TFM on 19:44, 16 February 16

Obviously you are incompetent reading the history in the CPCWike. I stated 50% from the beginning. Fano added his experience with 16.7%. But you are just trolling! Stop it!!!



No trace of :
Code: [Select]
Some CPCs (manufactured with fast DRAMs) show a increase of speed by 50% (verified with at least one CPC6128 produced 1987) until the last revision ....


Where you're wrong is by stating that Some CPCs (manufactured with fast DRAMs) show a increase speed by 50%.

All CPC are made equal  from the DRAM point of view, and if you where a bit more literate on HW, you would have been able to understand that.Be the visible speed increase 16 or 50% or any %, this speed is not tailored by the DRAM speed, nor the date of production. I have no idea of the real speed increase, but saying that some CPC will have different speed boost than other is just false.

In research domain, when you find a result that is in contradiction with the other scientist on the same experiment, your first task is to clarify that them and found who is wrong, not to publish your result and say on SOME blablabla ...
Title: Re: Does anyone have more information on 6 MHz CPC?
Post by: TFM on 19:45, 16 February 16
If someone could produce a video guide on how to do this and install a switch, I believe it would really help the CPC community.


Actually a good idea. Well, it's important to have a swtich for both pins of the crystal, but they are easily accessible and it doesn't need much solder skills. Maybe somebody can post a picture? (I can't at the moment).

Title: Re: Does anyone have more information on 6 MHz CPC?
Post by: gerald on 19:53, 16 February 16
Obviously you are incompetent reading the history in the CPCWike. I stated 50% from the beginning. Fano added his experience with 16.7%. But you are just trolling! Stop it!!!

Can you read  :picard2:
You added the following false statement (bold emphasis on the wrong part of the statement) : "Some CPCs (manufactured with fast DRAMs) show a increase speed by 50%"


The 50% increase is expected on all CPC.
Title: Re: Does anyone have more information on 6 MHz CPC?
Post by: TFM on 19:54, 16 February 16
Can you read  :picard2:
You added the following false statement (bold emphasis on the wrong part of the statement) : "Some CPCs (manufactured with fast DRAMs) show a increase speed by 50%"


The 50% increase is expected on all CPC.


Oh troll! That's what I told all the time! Don't you get it? Fano added the 16.7%! Here is what you wrote:

Does anyone have more information on 6 MHz CPC? (http://www.cpcwiki.eu/forum/technical-support/does-anyone-have-more-information-on-6-mhz-cpc/msg119929/#msg119929)


Thank's for turning another thread into a warfare. I quit this shit now, because what happen here is just beyond...


 :picard2: :picard2: :picard2: :picard2: :picard2: :picard2: :picard2: :picard2: :picard2: :picard2: :picard2: :picard2: :picard2: :picard2: :picard2:

Title: Re: Does anyone have more information on 6 MHz CPC?
Post by: gerald on 20:05, 16 February 16

Oh troll! That's what I told all the time! Don't you get it? Fano added the 16.7%! Here is what you wrote:

Does anyone have more information on 6 MHz CPC? (http://www.cpcwiki.eu/forum/technical-support/does-anyone-have-more-information-on-6-mhz-cpc/msg119929/#msg119929)


Thank's for turning another thread into a warfare. I quit this shit now, because what happen here is just beyond...


 :picard2: :picard2: :picard2: :picard2: :picard2: :picard2: :picard2: :picard2: :picard2: :picard2: :picard2: :picard2: :picard2: :picard2: :picard2:
So you keep on saying that you did not add the "Some CPCs (manufactured with fast DRAMs)" to the wiki.
And you obviously discussed with Fano about your results to understand why you got different ones , right ?
In case you're not understanding my point, I am questioning the way the speed increase are presented (some CPC will have more), not the values ...

From now, I let you on your thread.
In French we says : il n'y a pas pire aveugle que celui qui ne veut pas voir.
Title: Re: Does anyone have more information on 6 MHz CPC?
Post by: TFM on 20:07, 16 February 16
Und wie wir in Deutsch sagen: Du bist der K├Ânig der Spitzfindigkeiten!

Title: Re: Does anyone have more information on 6 MHz CPC?
Post by: PulkoMandy on 20:12, 16 February 16
Where you're wrong is by stating that Some CPCs (manufactured with fast DRAMs) show a increase speed by 50%.

Technically this statement is correct, until ALL CPCs have been tested and confirmed to work this way (which probably won't happen), the only thing we can say is that it works this way on some CPCs. That doesn't imply anything about the other CPCs, where this failed or was not tried. A lot of problems could arise, on early Gate Arrays which already generate a lot of heat at 4MHz, on pre-ASIC machines, or if the RAM or ROM are too slow to keep the rate.

However, I expect that it is either a 50% speed increase, or it doesn't work. 16% doesn't make much sense to me and I would expect something wrong with the experiment.
Title: Re: Does anyone have more information on 6 MHz CPC?
Post by: gerald on 20:36, 16 February 16
However, I expect that it is either a 50% speed increase, or it doesn't work. 16% doesn't make much sense to me and I would expect something wrong with the experiment.
It's 50% or nothing (ie crash). And crash will be visible quite soon.

This is what you will find on the wiki :
Quote
Some CPCs (manufactured with fast DRAMs) show a increase of speed by 50% (verified with at least one CPC6128 produced 1987).
In case of the older DRAM type the speed improvement is only 16.7%.

1. What I am pointing out is that chapter on the wiki wrongly that let think reader that they will either get 16% or 50% according to the speed of their CPC ram.
2. TFM added this 16% or 50 % rather than correct it to 50%. And he is saying that he did not make this change (or play foul to elude that fact that he overreact to any comment on his work)
 
Title: Re: Does anyone have more information on 6 MHz CPC?
Post by: 1024MAK on 20:42, 16 February 16
A better way of wording it is:-
You CPC may work with the higher speed crystal if the rest of the ICs are able to operate at this speed.


It would not be hard to work out if the DRAM chips are suitable, as the access time is in published data sheets. With the custom Amstrad ICs, it is rather harder to judge.


Mark
Title: Re: Does anyone have more information on 6 MHz CPC?
Post by: TFM on 20:45, 16 February 16
2. TFM added this 16% or 50 % rather than correct it to 50%. And he is saying that he did not make this change (or play foul to elude that fact that he overreact to any comment on his work)


Stop lying around! Fano added that! As great as your hardware is, as small your social skills are. Proof here:


Difference between revisions of "6 MHz CPC" - CPCWiki (http://www.cpcwiki.eu/index.php?title=6_MHz_CPC&type=revision&diff=68326&oldid=66964)
Title: Re: Does anyone have more information on 6 MHz CPC?
Post by: 1024MAK on 20:47, 16 February 16
It's 50% or nothing (ie crash). And crash will be visible quite soon.
Symptoms of the hardware not being happy are more likely failure to properly intialise to the start up screen.
Or symptoms similar to a RAM fault.

Mark
Title: Re: Does anyone have more information on 6 MHz CPC?
Post by: TFM on 20:48, 16 February 16
Symptoms of the hardware not being happy are more likely failure to properly intialise to the start up screen.
Or symptoms similar to a RAM fault.

Mark


Exactly, that's my personal experience too.
Title: Re: Does anyone have more information on 6 MHz CPC?
Post by: 1024MAK on 20:50, 16 February 16
And does it really matter who edited the wiki?

IMHO, it's more important to correct it. Not to argue about it.

Mark
Title: Re: Does anyone have more information on 6 MHz CPC?
Post by: gerald on 21:03, 16 February 16

Stop lying around! Fano added that! As great as your hardware is, as small your social skills are. Proof here:


Difference between revisions of "6 MHz CPC" - CPCWiki (http://www.cpcwiki.eu/index.php?title=6_MHz_CPC&type=revision&diff=68326&oldid=66964)
please define "that",
I cannot see anything that looks like "Some CPCs (manufactured with fast DRAMs)show a increase speed by 50%" in this link ....
Title: Re: Does anyone have more information on 6 MHz CPC?
Post by: andycadley on 21:36, 16 February 16
One day I'm going to get everyone from this forum into a room and we're all going to have a group hug. One that lasts just ever so slightly too long to be comfortable.

Just sayin'
Title: Re: Does anyone have more information on 6 MHz CPC?
Post by: SRS on 22:05, 16 February 16
One day I'm going to get everyone from this forum into a room and we're all going to have a group hug. One that lasts just ever so slightly too long to be comfortable.

Just sayin'

I'll stay outside and watch that all inside make their kindergarten-diploma before leaving ...  By the power of Greyskull!

(http://cdn.wegotthiscovered.com/wp-content/uploads/Masters-Of-The-Universe-e1375127888695.jpg)

BTW: is this c64 or cpc palette ? *lol*
Title: Re: Does anyone have more information on 6 MHz CPC?
Post by: Docent on 23:00, 16 February 16
please define "that",
I cannot see anything that looks like "Some CPCs (manufactured with fast DRAMs)show a increase speed by 50%" in this link ....
This is the correct link: Difference between revisions of "6 MHz CPC" - CPCWiki (http://www.cpcwiki.eu/index.php?title=6_MHz_CPC&diff=next&oldid=86639)
Title: Re: Does anyone have more information on 6 MHz CPC?
Post by: SRS on 23:39, 16 February 16
From my point of view ...

TFM wrote the "some ... 50%", which is correct. 16,x% was from Fano. Which seems not correct to most of us.

Either it is 50% or it crashes.

So if you define SOME as 0,1 to 100 %, it is correct.PulkoMandy (http://www.cpcwiki.eu/forum/profile/?u=26)stated this earlier. SOME will work 50% faster, SOME will crash. NO ONE will work at 16,6xxx ... until you proof it.

No reason to get picky on each other ... go back to lab and gimme a 4 GHz CPC !

SO - delete "fast DRAM" and "16,xx" from WIKI and the text will be more correct
Title: Re: Does anyone have more information on 6 MHz CPC?
Post by: TFM on 23:48, 16 February 16
From my point of view ...

TFM wrote the "some ... 50%", which is correct. 16,x% was from Fano. Which seems not correct to most of us.

Either it is 50% or it crashes.

So if you define SOME as 0,1 to 100 %, it is correct.PulkoMandy (http://www.cpcwiki.eu/forum/profile/?u=26)stated this earlier. SOME will work 50% faster, SOME will crash. NO ONE will work at 16,6xxx ... until you proof it.

No reason to get picky on each other ... go back to lab and gimme a 4 GHz CPC !

SO - delete "fast DRAM" and "16,xx" from WIKI and the text will be more correct


That's absolutely right. And I got no idea if different CPCs used different RAM chips or not, it may be one issue, the GA or CRTC may be another one. Ok, working on the 4 GHz CPC now... tell you first results in 2086 or so.  ;)
Title: Re: Does anyone have more information on 6 MHz CPC?
Post by: ukmarkh on 23:50, 16 February 16
I'm sure if we all met for a beer, we'd laff about all this, and design a super CPC  :laugh:
Title: Re: Does anyone have more information on 6 MHz CPC?
Post by: gerald on 00:29, 17 February 16
TFM wrote the "some ... 50%", which is correct. 16,x% was from Fano. Which seems not correct to most of us.
No, TFM changed
Code: [Select]
This speed improvement is 16.66667%.This has been tested with this simple programto
Code: [Select]
Some CPCs (manufactured with fast DRAMs) show a increase of speed by 50% (verified with at least one CPC6128 produced 1987).
 In case of the older DRAM type the speed improvement is only 16.7%
While he should have just change to
Code: [Select]
This speed improvement is 50%.This has been tested with this simple program (verified with one CPC6128)
Everything else is just wrong.
And this section is not discussing the success rate of the modification.

And I got no idea if different CPCs used different RAM chips or not, it may be one issue, the GA or CRTC may be another one.
You got no idea, but by stating that it gives 50% more speed on CPC with faster DRAM and also stating that slower DRAM will result in less performance gain, you just build a theory to explain why fano get on 17% :
- my cpc has fast DRAM and can run 50%. Fano only get 17% so he must have slower DRAM.

CPC use 200ns / 150ns or even 120ns, but you can check on the motherboard page that the speed in not function of production year.
150ns can be found on early 464 as well as pre-asic 6128. 120ns is mainly use on the plus range.

Now, let fix that page do something more interesting  ;)



Title: Re: Does anyone have more information on 6 MHz CPC?
Post by: SRS on 00:35, 17 February 16
While he should have just change to
Code: [Select]
This speed improvement is 50%.This has been tested with this simple program (verified with one CPC6128)
Well, is there NO WIKI-Admin that could change it , now ?
Title: Re: Does anyone have more information on 6 MHz CPC?
Post by: TFM on 00:54, 17 February 16
What I changed happened in agreement with others back the day. I'm not just deleting a value which I can not prove right or wrong. Please everybody feel free to improve the article.  :)