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Soft ps mod for hard ps macs & apple II's

Looking at the timing diagrams beginning on page 28, its kinda confusing a little bit.

The Synchronous read and write bus operations, I could clearly go off just the /AS /DS R/W and the /DBEN signals by themselves if you wanted to, as they ensure the address and or data is valid at the time these signals get asserted. But again, the listening MCU would have be at least 4 times the speed of the bus/CPU. I guess this is why just about every expansion card back in the day had a CPLD/FPGA or glue logic. an AVR wouldnt be bad because its a near 1 to 1 execution to clock ratio but the max speed a standard AVR goes up to is 20mhz.

The Asynchronous reads and writes are way different, have to pay attention to the falling edge of the clock to get the proper data bits. nothing really else to look for that I can see.

 
Hows progress?

I havent really anything helpfull to add, I'm still following this,

i havent lost interest - especially in an apple IIGS version ;)

from what i read, i understand correctly technight, that you like the idea of having a mcu basically being capable of controlling the softpower and kb startup/finder shutdown for most hardpower mac models excluding the mac+ and earlier(and hopefully the IIGS - had to add that ;) ) all on one chip?

 
Cool :)

Would you be willing to intergrate a non-software boot function of the mcu for what was discussed earlier with trash80tohpmini earlier for 8 bit apples? - pressing down reset button for a soft boot and press and hold reset for a few seconds to powerdown?

as the os (prodos) is only a simple cli.

Tho having said that, if a register is provided. Using 8 bit 'appleIIDesktop' would become way cooler, with a simple shutdown app writing to the register shuts down the machine when the a2desktop gui (its not a full os , just a desktop that sits on top of the os.

Another thought, maybe also u could - if it is a simple matter - only for completeness later on maybe, u could program ur mcu to respond to a simple keypress combo for early macs eg apple delete or something,as long as the finder doesnt own tht key combo, it could be used to hard shutdown the system fter the shutdown menu item has been run. just a few ideas...

 
i know nothing about the apple II line. :-(

key combos would require you to be able to decode the ADB system. the power button on an ADB keyboard is a separate line.

 
oh interesting! the reset/power key is separate!

in the 3rd paragraph i was refering to early macs without adb or the power key.

 
but it was just an idea. Not that it was my idea, but i realise i might have come across as pushy. I apologise for this, sorry mate.

 
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