On the STM32H (not L) I need to use a 1-wire EPROM, and I try the generic driver calls generated by the IDE (HAL_SWPMI_Receive, HAL_SWPMI_Transmit, HAL_SWPMI_MspInit, etc.) and I see no bits going out on the scope, and the transmit times out.

[PBrai.1]

I can "Transmit" but the TXE flag never clears and the transmit times out. It's unclear which parts of the bus are fully automated (reset, discovery, etc.) and how much of the CRC is handled, etc. I can see nothing on a scope, but if the chip gets in an odd state and never tries to send that would match what I'm seeing. Without better register descriptions or some example that can talk to a 1wire EPROM I'm kinda stuck.

[Tesla DeLorean]

All the peripheral and pin clocks are enabled?

Are all the peripheral registers reporting zero?

[Tesla DeLorean]

The STM32H7xx of some description? It helps to be very specific as there are literally thousands of STM32 parts, and at least half a dozen different H7 die in circulation.

Show the salient peripheral, pin, clock initialization code, and usage.

https://st-onlinetraining.s3.amazonaws.com/STM32H7-Peripheral-Single-Wire-Protocol-Master-Interface_%28SWPMI%29/index.html