Hi lolita, and good monday! :roll:
Quote:
Originally Posted by lolita";p="
Inspecting the schematics and datasheets for the 7515, it seems that CE5 is the same pin as what would be GPO A3, so it is likely a multifunction pin. Try setting bit 3 of EE (GPO A port) to see if CE5 does enable. If it does, then the pin is not in CE mode but in GPO mode.
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Nope... setting GPO A3 bit (i.e.
"o ee 8") seems to not affect the CE5 pin... :evil:
Quote:
Originally Posted by lolita";p="
Which CE gets activated when you write 28 to port 2? Only one can be active at a time, and if all the external ones are disabled then CE0 is enabled, which only selects the internal boot ROM.
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Always assuming an electrical problem on CE5 line, with the help of
the Samsung's NAND flash datasheet (page 4), I've traced the CE- pin and I've found that it's connected to the pin 43 (CE1) of the CPU, as described in the ACU7515 schematic (U2 chip at upper right, with CE2 line not used).
At this point, because
"Only one can be active at a time", I've tried to select the CEx lines in order to show some variations on this pin:
Code:
o 2 00 ; CE1 = +3.03 volts
o 2 08 ; CE1 = +3.03 volts
o 2 10 ; CE1 = +3.03 volts
o 2 18 ; CE1 = +3.03 volts
o 2 20 ; CE1 = +3.03 volts
o 2 28 ; CE1 = +3.03 volts
It's very strange... it seems that the
"o 2 xx" command does nothing on the CEx lines... :?:
In order to exclude any doubt about the proper functioning of the CE1 line I did another test: I've plugged the player into the PC (USB drive mode), then I've copied a big file into the flash memory, following the CE pin of the flash with the digital multimeter: the voltage was fluctuating (as a rapid enable/disable of the chip), returning to +3.03 volts (chip disabled) after the copy finished. So, the CE1 line seems to work correctly.
Can be that the command
"o 2 xx" does not work because it need some "initialization" before?