Trying to figure out which NOR chip to buy for my ZeroPi is giving me a headache. FriendlyArm has very little info available on what works. The board has an empty spot to solder a NOR chip that I would like to populate. There are so many chips all with different voltages and clock frequencies. The wiki and schematic omit the connection all together so I really have no idea what would work. Can someone point me in the right direction? 

 

 

3 minutes ago, stut said:

Can someone point me in the right direction?

Most of them are working as long as they are 2.7V and above. Frequency is not really an issue since in DT it is usually set 40MHz and could be lowered manually by editing DTS.

I've used Winbond ones on both my OPiZeros and OPiPC2. So, I suggest Winbond one, but maybe also GigaDevice.

On 3/16/2020 at 12:33 PM, martinayotte said:

I've used Winbond ones on both my OPiZeros and OPiPC2. So, I suggest Winbond one, but maybe also GigaDevice.

 

I would agree that Winbond is better supported in uBoot - GD is good, but not 1 for 1 replacement.

10 hours ago, sfx2000 said:

but not 1 for 1 replacement.

What are the differences ?

11 hours ago, martinayotte said:

What are the differences ?

 

Because they are not one for one replacements on the SPI-NOR...

 

sfx

12 hours ago, sfx2000 said:

Because they are not one for one replacements on the SPI-NOR...

But again, what are the differences that you found ?

(I was looking quickly at both GigaDevice and Winbond datasheets, and I didn't found any difference until now)

14 hours ago, martinayotte said:

But again, what are the differences that you found ?

 

Based on work with OpenWRT - mostly with how the chip is ID'd

 

Geometry is the same - I would go with Winbond myself, as it's more understood if folks run into problems.

10 hours ago, sfx2000 said:

mostly with how the chip is ID'd

If you look at U-Boot drivers/mtd/spi/spi-nor-ids.c, you will see that GigaDevice are well supported ...