Let me present the A3660 - Page 2

Mathesar · 21 February 2018, 20:20

In follow up to the discussion here: http://eab.abime.net/showthread.php?t=87971&page=10 about the pclk/bclk/cpu_clk/clk90 timing I am looking at the files provided by Chucky to see if I can modify the PCB to support other clock chips.

I am bit puzzled about the _clken timing of the 060 though. The 060 user manual states that _clken can be derived from bclk by delaying it for 5ns IF the blkc and the pclk have zero skew. On the A3640 however there is already about 5ns skew between bclk and pclk ( as meausred here by Amiga87: http://eab.abime.net/showpost.php?p=...&postcount=193.
But the 060 adapter (and thus also the A3660) delays bclk by an additional 5ns before feeding it into the _clken pin of the 060. So, the total delay is almost 10ns. Clearly it still works as demonstrated by Chucky and others but still I wonder if this isn't a mistake in the original 040/060 adapter schematic.

Anyone has an idea?

zerohp · 21 February 2018, 22:23

I had the same question a while back and checked a unmodified A3640 with my oscilloscope. There is a 5 ns skew already. The adapter should include it for other boards, but I am not sure if it's necessary for the 3640. I want to test the theory but I haven't had time.

Amiga87 · 22 February 2018, 00:31

Quote:

Originally Posted by zerohp

The adapter should include it for other boards, but I am not sure if it's necessary for the 3640.

Probably not necessary, but it doesn't hurt. The 060 samples the clken (040 bclk) on the rising edge of clk. So a little extra margin doesn't hurt.

A87

elenachen · 05 April 2018, 17:16

Someone got 2 PCB's of the A3660? Did you already release the Rev 1 Board?

Chucky · 05 April 2018, 17:17

the rev 1 have been out since Amiga32..

I have also got 1.1 boards. not been able to test them yet

plasmab · 05 April 2018, 17:22

I have one Mwhahahaha

Chucky · 05 April 2018, 17:23

you do not have the 1.1 mowahahhahaha

SpeedGeek · 05 April 2018, 17:44

Quote:

Originally Posted by Mathesar

In follow up to the discussion here: http://eab.abime.net/showthread.php?t=87971&page=10 about the pclk/bclk/cpu_clk/clk90 timing I am looking at the files provided by Chucky to see if I can modify the PCB to support other clock chips.

I am bit puzzled about the _clken timing of the 060 though. The 060 user manual states that _clken can be derived from bclk by delaying it for 5ns IF the blkc and the pclk have zero skew. On the A3640 however there is already about 5ns skew between bclk and pclk ( as meausred here by Amiga87: http://eab.abime.net/showpost.php?p=...&postcount=193.
But the 060 adapter (and thus also the A3660) delays bclk by an additional 5ns before feeding it into the _clken pin of the 060. So, the total delay is almost 10ns. Clearly it still works as demonstrated by Chucky and others but still I wonder if this isn't a mistake in the original 040/060 adapter schematic.

Anyone has an idea?

No, it's not a mistake. The 060 adapter was not designed for the A3640. It was designed for 040 accelerators which provide BCLK to PCLK skew compensation.

I also warned users about skew compensation (many times) here:

http://eab.abime.net/showthread.php?...=a3640+franken

I also warned Mozart over at A1k.org many years ago...

Will, I continue to give any more warnings? No, but I will be happy to continue using my A3660 @ 80 MHz!

elenachen · 05 April 2018, 17:48

Quote:

Originally Posted by Chucky

you do not have the 1.1 mowahahhahaha

Yep, i meant those! But then they're not confirmed working yet. Whats the difference between Rev 1 and 1.1?

Chucky · 05 April 2018, 17:51

Quote:

Originally Posted by elenachen

Yep, i meant those! But then they're not confirmed working yet. Whats the difference between Rev 1 and 1.1?

the 1.1 got choises for 2 different clockdrivers and 2 different delaylines

elenachen · 05 April 2018, 18:18

Hmm, probably take 1.0 Boards then, can't have 2 variables here. Have to got something reliably working, since I'll build the Mainboard myself^^ What do you want for 2 of the PCB's?

Chucky · 05 April 2018, 18:20

for you 4000 project.. hell send me a PM with your address and I ship you some..

for free..

elenachen · 05 April 2018, 18:22

Quote:

Originally Posted by Chucky

for you 4000 project.. hell send me a PM with your address and I ship you some..

for free..

Wow, that would be really nice!

plasmab · 05 April 2018, 19:19

Quote:

Originally Posted by Chucky

you do not have the 1.1 mowahahhahaha

Oooh. Can I have one?

Chucky · 05 April 2018, 19:31

can be solved

tnt23 · 10 April 2018, 21:49

Should the 3660 work in A3000 where A3640 lived happily? Same motherboard jumpers settings, unmodified KS3.1?

Chucky · 10 April 2018, 21:52

with a 040.. yes.
with 060 (with FPU) it requires a custom kickstart

tnt23 · 10 April 2018, 22:07

Could this be the reason it won't even start with full 060RC50? Power LED stays dim.

Chucky · 10 April 2018, 22:10

No. .it should guru-flash..

on ALL boards sent to me with "bo boot" on the A3000. it havebeen R401 not being soldered on ok. (but working on 4000 etc)

also a quite common thing is bad delayline chips or 74f04 / 74F1803s.. (74f803)

tnt23 · 10 April 2018, 22:17

Thanks Chucky, I will double check the chips in question. R401 is in place, it was in fact R101 that I have soldered incorrectly first (put both 5ns and 10ns links

)

21 February 2018, 20:20	#21
Mathesar Registered User Join Date: Aug 2014 Location: Netherlands Posts: 695	060 adapter _clken timing? In follow up to the discussion here: http://eab.abime.net/showthread.php?t=87971&page=10 about the pclk/bclk/cpu_clk/clk90 timing I am looking at the files provided by Chucky to see if I can modify the PCB to support other clock chips. I am bit puzzled about the _clken timing of the 060 though. The 060 user manual states that _clken can be derived from bclk by delaying it for 5ns IF the blkc and the pclk have zero skew. On the A3640 however there is already about 5ns skew between bclk and pclk ( as meausred here by Amiga87: http://eab.abime.net/showpost.php?p=...&postcount=193. But the 060 adapter (and thus also the A3660) delays bclk by an additional 5ns before feeding it into the _clken pin of the 060. So, the total delay is almost 10ns. Clearly it still works as demonstrated by Chucky and others but still I wonder if this isn't a mistake in the original 040/060 adapter schematic. Anyone has an idea?

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21 February 2018, 22:23	#22
zerohp Registered User Join Date: Dec 2017 Location: Champaign, IL / USA Posts: 7	I had the same question a while back and checked a unmodified A3640 with my oscilloscope. There is a 5 ns skew already. The adapter should include it for other boards, but I am not sure if it's necessary for the 3640. I want to test the theory but I haven't had time.

05 April 2018, 17:16	#24
elenachen Registered User Join Date: Feb 2018 Location: Nürnberg Posts: 97	Someone got 2 PCB's of the A3660? Did you already release the Rev 1 Board?

05 April 2018, 17:17	#25
Chucky Registered User Join Date: Mar 2015 Location: Karlstad / Sweden Age: 52 Posts: 1,210	the rev 1 have been out since Amiga32.. I have also got 1.1 boards. not been able to test them yet

05 April 2018, 17:22	#26
plasmab Banned Join Date: Sep 2016 Location: UK Posts: 2,917	I have one Mwhahahaha

05 April 2018, 17:23	#27
Chucky Registered User Join Date: Mar 2015 Location: Karlstad / Sweden Age: 52 Posts: 1,210	you do not have the 1.1 mowahahhahaha

05 April 2018, 18:18	#31
elenachen Registered User Join Date: Feb 2018 Location: Nürnberg Posts: 97	Hmm, probably take 1.0 Boards then, can't have 2 variables here. Have to got something reliably working, since I'll build the Mainboard myself^^ What do you want for 2 of the PCB's?

05 April 2018, 18:20	#32
Chucky Registered User Join Date: Mar 2015 Location: Karlstad / Sweden Age: 52 Posts: 1,210	for you 4000 project.. hell send me a PM with your address and I ship you some.. for free..

05 April 2018, 19:31	#35
Chucky Registered User Join Date: Mar 2015 Location: Karlstad / Sweden Age: 52 Posts: 1,210	can be solved

10 April 2018, 21:49	#36
tnt23 Registered User Join Date: Feb 2008 Location: Saint-Petersburg / Russia Posts: 324	Should the 3660 work in A3000 where A3640 lived happily? Same motherboard jumpers settings, unmodified KS3.1?

10 April 2018, 21:52	#37
Chucky Registered User Join Date: Mar 2015 Location: Karlstad / Sweden Age: 52 Posts: 1,210	with a 040.. yes. with 060 (with FPU) it requires a custom kickstart

10 April 2018, 22:07	#38
tnt23 Registered User Join Date: Feb 2008 Location: Saint-Petersburg / Russia Posts: 324	Could this be the reason it won't even start with full 060RC50? Power LED stays dim.

10 April 2018, 22:10	#39
Chucky Registered User Join Date: Mar 2015 Location: Karlstad / Sweden Age: 52 Posts: 1,210	No. .it should guru-flash.. on ALL boards sent to me with "bo boot" on the A3000. it havebeen R401 not being soldered on ok. (but working on 4000 etc) also a quite common thing is bad delayline chips or 74f04 / 74F1803s.. (74f803)

10 April 2018, 22:17	#40
tnt23 Registered User Join Date: Feb 2008 Location: Saint-Petersburg / Russia Posts: 324	Thanks Chucky, I will double check the chips in question. R401 is in place, it was in fact R101 that I have soldered incorrectly first (put both 5ns and 10ns links )

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