04-07-2012, 09:04 AM
I had a look at some of the docs for those manufacturers and can't find any other method to remove the protection either.
The reason I'd like to be able to flash the carts is mostly to avoid bit rot - the carts are getting older and are already past the half way point of the data retention period given by Sharp.
Anyway, I would love to buy a flash cart with an microSD card slot, so if you are working on those, thats great
If you find time to experiment with the old carts, the documents mention a minimum rise time for the voltage on the reset pin to reach the 12V. I imagine this is to avoid the voltage overshooting for a fraction of a second as the connection is made, or to avoid high frequency harmonics. Maybe in an experiment a pot could be used to slowly raise the voltage, or a small capacitor could be placed between the reset pin and ground, to act like a low-pass filter and slow the rise time.
The old carts could be modified by adding an un-protect switch that switches the reset pin between VCC and one of the unused cart pins, and in the linkmasta that pin could be set to 12V when writing.
The reason I'd like to be able to flash the carts is mostly to avoid bit rot - the carts are getting older and are already past the half way point of the data retention period given by Sharp.
Anyway, I would love to buy a flash cart with an microSD card slot, so if you are working on those, thats great
If you find time to experiment with the old carts, the documents mention a minimum rise time for the voltage on the reset pin to reach the 12V. I imagine this is to avoid the voltage overshooting for a fraction of a second as the connection is made, or to avoid high frequency harmonics. Maybe in an experiment a pot could be used to slowly raise the voltage, or a small capacitor could be placed between the reset pin and ground, to act like a low-pass filter and slow the rise time.
The old carts could be modified by adding an un-protect switch that switches the reset pin between VCC and one of the unused cart pins, and in the linkmasta that pin could be set to 12V when writing.