So, I got myself all the TTL ICs that were supposed to be defective on the motherboard, I burned a new UVPROM with a French video generator, plus I made some corrections on the board :
After having done this modifications, again, nothing worked, exept a flashing white/black screen. At this stage, an very imortant thing : To start, an Apple //e need to have its keyboard attached!
After have plugged the connector of the keyboard and switched on again, TaDa :
The first Propgramm since... a very long time. |
In this configuration, the main board is equiped with a 64K Apple memory card and runs the basic interpreter as soon as power is turned on : great!
Now, I have to put this main board with the PSU and the keyboard back into the original case, and to test the two floppy drives with the expansion board.
PSU |
Main Board |
Keyboard |
Ext Cards |
And after have placed the cover and powered this Apple //e :
Yessssss |
The 74LS125 burned without reason. A check of the voltage revealed a very good value of 4,97V on it! I never saw that befor, exept with the good reason of overvoltage.
The trace of smoke deposited on the top of the floppy drive indicates that the 74ls125 has reached a very high temperature... So I replaced it with a new one :
Finally, the system works very well with the two drives attached on it :
CTRL + CLOSED APPLE + RESET or APPLEs at POWER UP |
But I don't have any Pro DOS floppy to boot with. And I don't know how to find that! Actually I must stop the boot process with the CTRL/RESET keys and go to the internal Basic interpreter. A good solution could be the use of an Apple // disk drive emulator like this :
Extension cards for the Apple II?
https://quip.com/ :
ADP Pro :
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