I'm looking at how to do clock generation for the next revision of the TF360....
I'd like to be able to get a bunch of frequencies out selectable by something simple. I spotted this one but i'm not dead set on it..
https://uk.rs-online.com/web/p/pll-freq ... s/1703521/
I'm open to opinions on this but i'm not going to use a chip that needs programmed via SPI/I2C etc. Thats too complex to do in the CPLDs.
EDIT: This one is also good
https://uk.rs-online.com/web/p/pll-freq ... s/1628970/
With 25Mhz crystal input we could have the TF360 boot at 50Mhz by default but then have a command line app that could ramp you up to a bunch of options such as..
62Mhz
75Mhz
78Mhz
80Mhz
100Mhz
Clock generator for TF360 rev 1
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Clock generator for TF360 rev 1
———
"It is not necessarily a supply voltage at no load, but the amount of current it can provide when touched that
indicates how much hurting you shall receive."
"It is not necessarily a supply voltage at no load, but the amount of current it can provide when touched that
indicates how much hurting you shall receive."
Re: Clock generator for TF360 rev 1
This would be excellent. Especially when most of the time the higher clock speeds are not needed (ie a WHDLoad gaming session with 2D based games). This also would certainly help with heat on the A1200 application. This would also solve the "I bought the 78Mhz version but my 060 wont do that, can I send back my TF360 for 50Mhz version".
Superduper etc can then guarantee a card that will work at 50Mhz but depending on setup 100Mhz is possible.
The Warp1260 guys said they were also having adjustable clock speed, dont know how they are doing it though. A picture of their populated PCB might yield the answer.
Superduper etc can then guarantee a card that will work at 50Mhz but depending on setup 100Mhz is possible.
The Warp1260 guys said they were also having adjustable clock speed, dont know how they are doing it though. A picture of their populated PCB might yield the answer.
- 8 Bit Dreams
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Re: Clock generator for TF360 rev 1
i do remember that ive thinkered with IDT ICS 570AILF, it's 5V chip so may be perfect for retro hardware
https://www.idt.com/document/dst/570-datasheet
Digi-Key part numper: 800-2373-5-ND
this multiplier can also have several profiles switched by resistor/jumper settings,
don't know will it fit Your needs or not..
https://www.idt.com/document/dst/570-datasheet
Digi-Key part numper: 800-2373-5-ND
this multiplier can also have several profiles switched by resistor/jumper settings,
don't know will it fit Your needs or not..
Retro computer hardware & repair in Germany
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Re: Clock generator for TF360 rev 1
I will never sell an option like that. Its my idea of hell."I bought the 78Mhz version but my 060 wont do that, can I send back my TF360 for 50Mhz version".
They're using an FPGA which probably has a clock generator tile in the fabric.The Warp1260 guys said they were also having adjustable clock speed, dont know how they are doing it though. A picture of their populated PCB might yield the answer.
Yeah i didnt get on well with that chip for some reason. I cant remember why.8 Bit Dreams wrote: ↑Sun Sep 08, 2019 1:42 pm i do remember that ive thinkered with IDT ICS 570AILF, it's 5V chip so may be perfect for retro hardware
https://www.idt.com/document/dst/570-datasheet
Digi-Key part numper: 800-2373-5-ND
this multiplier can also have several profiles switched by resistor/jumper settings,
don't know will it fit Your needs or not..
I dont actually need the zero delay part because the reference clock is fed into the CPLD and it does complex clock generation from there.
EDIT: I remember why i didnt like that chip.. when connected to a tri-stated pin the M value in that truth table didnt work.
———
"It is not necessarily a supply voltage at no load, but the amount of current it can provide when touched that
indicates how much hurting you shall receive."
"It is not necessarily a supply voltage at no load, but the amount of current it can provide when touched that
indicates how much hurting you shall receive."
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Re: Clock generator for TF360 rev 1
There is also "B" version of this chip with the only difference that it runs with 3.3V instread of 5V..
need to admit this would be very nice feature - to make clock switchable, will save a lot of hassle and headache
need to admit this would be very nice feature - to make clock switchable, will save a lot of hassle and headache
Retro computer hardware & repair in Germany
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Re: Clock generator for TF360 rev 1
So I’ve thought about this a little...
The TF360 will default to 50Mhz... I will provide a tool to let you change it and a library module that will read the settings from nvram and update during boot.
This is likely to mean you’ll need a new ROM to take advantage of this unless I can squeeze a module into the cpld
Basically your TF360 settings will look like a game slot.
The TF360 will default to 50Mhz... I will provide a tool to let you change it and a library module that will read the settings from nvram and update during boot.
This is likely to mean you’ll need a new ROM to take advantage of this unless I can squeeze a module into the cpld
Basically your TF360 settings will look like a game slot.
———
"It is not necessarily a supply voltage at no load, but the amount of current it can provide when touched that
indicates how much hurting you shall receive."
"It is not necessarily a supply voltage at no load, but the amount of current it can provide when touched that
indicates how much hurting you shall receive."
Re: Clock generator for TF360 rev 1
Looks like a feature creep...
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Re: Clock generator for TF360 rev 1
I’m balancing this against the sodomization that will occur to boards if end users have to do smd soldering to change speed.
———
"It is not necessarily a supply voltage at no load, but the amount of current it can provide when touched that
indicates how much hurting you shall receive."
"It is not necessarily a supply voltage at no load, but the amount of current it can provide when touched that
indicates how much hurting you shall receive."
Re: Clock generator for TF360 rev 1
How about adding a few jumpers instead?terriblefire wrote: ↑Mon Sep 09, 2019 10:23 am I’m balancing this against the sodomization that will occur to boards if end users have to do smd soldering to change speed.
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Re: Clock generator for TF360 rev 1
Yeah...
or blobs of solder
or blobs of solder
Retro computer hardware & repair in Germany