Rustynutt wrote:Thanks for the input. We are both talking about the same things.
Rustynutt wrote:I want to change the pin arrangement so the 040 on the installed Apple card is getting the same PCLK as it would on the Afterburner without the Apple card.
Rustynutt wrote:Skew is negligible on those chips, so will run the AB PCLK to a 1X output on the Apple divider.
Rustynutt wrote:Basically, a test to make sure the Apple "Quad Doubler 25MHz/50MHz" card will work with the AB 040 as an adapter of sorts. Even though it will be the same speed as the Afterburner without the apple card, this would tell me if there is an issue with the resistor arrangement for power and clock signals with the Apple card placed in the Afterburner CPU socket. My gut feeling is, there should not be an issue as this is also how it fits into the Quadras. All guess work lacking the proper test equipment, but that's how Spock arrived at many solutions .
Rustynutt wrote:There is a feature the divider on Apple card includes, not available on the divider on the AB, which holds the CPU clocks in reset for a specified duration to allow the clock signals to obtain phase lock on chip before releasing the signal to the processor. Don't know how critical this is in real world applications with the 040, or maybe the PAL on the Afterburner takes care of it . That being the case, there could be noticeable skew between the BCLK on the AB and signal going out to the 040 after RST and PLL is achieved. If the PAL is doing this as well, might be a problem to detect without a good scope. If not, replacing the divider on the AB with one spec'ed for the 060 timing, and bypassing the divider on the Apple card should take care of that. Another concern is how the COMBEL handles clock division internally, as I would like to put the 060 divider right off the oscillator from the Nemesis, and feed it to the COMBEL and bypass it's 32 MHz clock signal to the expansion pin, DMA and everything else running at 32MHz on the board. The other COMBEL clocks are slow enough that I don't think that would be a problem. For now, will stick with them on the accelerator cards first to verify it works.
Rustynutt wrote:The other Apple card, a DiiMOCache 050, uses the same clock divider as the Afterburner. It also has a bunch logic on the board, assume it is for the additional Cache. Think another mistake I made was referring to that as L2 Cache, isn't that the CPU cache, or is it the term for memory available outside the CPU? Anyway, will play with it some after testing with the other card.
Rustynutt wrote:What got me started on this 8 years ago was after I purchased the Interconnect 060 adapter, couldn't figure out why it didn't work on the Afterburner. I'd read somewhere that in the first few lines of TOS there is some incompatible code. I took off that direction by having a coworker burn TOS onto a chip I mounted on a card to fit the cartridge port. Forget whom it was at the time, an Atarian from either Poland or Czechoslovakia (Peter S ?) provided a TOS image which was suppose to have the one or two lines of code modified to work. Never got anywhere with that effort, honestly way above my head and understanding. Think this was just after the time Titan kind of dropped out of the picture and began what I recall was website design or something.
Rustynutt wrote:More recently, when reading about the Milan's requirement for an adapter card that not only provides 3.3V and ties a couple pins together on the 060, there was an additional requirement to delay the CPU from starting during power up and reset functions. This was a function the Interconnect socket does not provide. With the Milan adapter no longer available, tried to implement that circuit on the Interconnect socket without success.
rpineau wrote:Has anyone ever got the schematics for the Milan 68060 processor adapter ?
rpineau wrote:So I'll see what I can do sometimes this week or next weekend.
rpineau wrote:In any case I'll be happy to help in any way (I have the latest know source code for the AB040 toolkit if someone is also interested in these).
rpineau wrote:The source I have are the original source sent to me (I don't remember who send them to me, from memory it was the original author but that was a few years ago).
So the source are properly commented. The version I have is 5.08 with the Eclipse fix.
rpineau wrote:AS to putting a 68060 on the AB040 we will probably need to find a way to get the Motorola 68060_lib code in there as the 68060 is missing some instructions that are software emulated (the source are available from Motorola web site and I have them if they are no longer there).
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