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Date: Thu, 19 Feb 2015 19:12:18 +0100
From: Sylvain Rochet <gradator@gradator.net>
To: Maxime Bizon <mbizon@freebox.fr>
Cc: Pantelis Antoniou <pantelis.antoniou@konsulko.com>,
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Hello,

On Thu, Feb 19, 2015 at 07:01:59PM +0100, Maxime Bizon wrote:
> On Thu, 2015-02-19 at 19:38 +0200, Pantelis Antoniou wrote:
>=20
> > Having to boot and tweak the bootloader settings to select the correct
> > dtb (even if it=E2=80=99s present on the flash medium) takes time and is
> > error-prone.
>=20
> Dedicate a set of GPIO for board/PCB revision detection (it only costs a
> few resistors connected to VCC or GND), then use that information to
> choose the correct DTB.

Or use a 1-wire or I2C EEPROM to store your board information.

Or, even better, if you have an I2C device, just chose a different=20
address on each board for this device and then probe I2C devices in your=20
boot loader until you found one you are looking for, this way, you don't=20
need spare GPIO at all. You don't even need to populate the same I2C=20
device on all boards, you can actually probe anything.

Sylvain

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