On Mon, Jul 12, 2021 at 02:33:58PM +0100, Russell King (Oracle) wrote:

On Mon, Jul 12, 2021 at 04:06:24PM +0300, alexandru.tachici@analog.com wrote:

quoted

From: Alexandru Tachici <redacted>

The ADIN1100 is a low power single port 10BASE-T1L transceiver designed for
industrial Ethernet applications and is compliant with the IEEE 802.3cg
Ethernet standard for long reach 10 Mb/s Single Pair Ethernet.

Ethtool output:
        Settings for eth1:
        Supported ports: [ TP	 MII ]
        Supported link modes:   10baseT1L/Full
                                2400mv
                                1000mv

The SI unit of voltage is V not v, so milli-volts is mV not mv. Surely,
at the very least, we should be using the SI designation in user
visible strings?

It may also be worth providing a brief description of 10BASE-T1L in the
cover letter so (e.g.) one doesn't have to look up the fact that the
voltage level is negotiated via bit 13 of the base page. I've found
that by searching google and finding dp83td510e.pdf

I'm curios how the voltage should be actually chosen?

In the adin1100 datasheet i read:
"The 1.0 V pk-pk operating mode, external termination resistors and independent
Rx/Tx pins make the ADIN1100 suited to intrinsic safety applications"

"For long reach/trunk applications the higher transmit amplitude of 2.4 V pk-pk"

So, it seems to depends on:
- do we have safety requirements?
- how long is the cable?

Can we use 2.4V any time if it is available or it is bad idea for short
cables?

Regards,
Oleksij
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