Configuring IEEE test modes on SPEBlox and SPEBlox Longs

– Copied from customer email –

Do your boards have MDIO access to the Ethernet PHY? Specifically I’m wondering if test pattern transmission can be forced. The IEEE defines “Test Modes” for electrical compliance testing. Test Modes are typically enabled through PHY register writes via MDIO (or equivalent) interface.

For SPEBlox, yes you can enable test modes on the DP83TG720S-Q1 1000BASE-T1 device. This is possible because SPEBlox contains a small STM32 microcontroller, and firmware can be written to that to enable the test modes over the MDIO bus. This is either something we can configure for you, or we can give you the information to write this firmware yourself.

For SPEBlox Long, we use the DP83TD510E for the 10BASE-T1L which (after inspecting the datasheet), also allows test patterns. Again, this can be enabled through custom firmware on the onboard STM32.

Reach out to us on if you’d like information on configuring the firmware yourself, or whether you’d like us to do that for you.