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BlueSCSI / BlueSCSI-v2

Open source, open hardware, SCSI emulator using the Pi Pico PR2040
https://bluescsi.com
GNU General Public License v3.0
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Dataloss at PowerBook board (possible solution provided) #21

Closed schreinerman closed 1 year ago

schreinerman commented 1 year ago

Currently I have data losses at PowerBook 170.

I will try to have a fix for this issue.

1) I'm preparing to add additional capacitors to 5V (2x 6.3V/1000uF), 3.3V (3x 6.3V/1000uF) and 2.8V (1x 6.3V/1000uF). 2) Raspberry Pi Pico can detect via GPIO24 if a voltage is present, GPIO29 (ADC3) can measure the voltage via ADC. If the VSYS voltage drops below 3V, the SD-Card should be synced and read/write should be stopped to prevent data losses.

androda commented 1 year ago

Hello,

It sounds like you are planning to add capacitance to the various voltage rails. Have you done any measurements of the input 5v sources and the output 3.3 / 2.85 rails to see if and how much they may be drooping?

schreinerman commented 1 year ago

I did not made any measurements yet. The Pico can be powered from 1.8 - 5.5V, so lower voltages than 5v are not a big issue. The Pico contains a buck-boost converter which is stabilizing the voltage to 3.3V. 2.85V for the drivers should be normally also not the big deal, because the LDO requires around 4V as minimal input voltage.

Anyhow: With all the capacitors I don't have any data losses anymore.

See some picture attached.

image

androda commented 1 year ago

I'm glad you were able to resolve the issue. This is the first and only report of data loss on the PowerBook version, and I have been unable to duplicate it.