After many hours of testing, I finally found a firmware that works.
I currently use "Antminer-Z9-Mini-NAND-500M-201808311812-unlocked-factory.tar.gz" firmware.
When booting all 4 hashboards are detected. Unfortunately, not everything is displayed correctly in the web interface. There are missing temperature values, hashboard values and fan values.
But that is not a problem, I connected via ssh to the miner and have there manually by:
cgminer-api -o stats | sed 's/,/\n/g' | grep 'temp1=|temp2=|temp3=|temp4=|temp2_1=|temp2_2=|temp2_3=|temp2_4=|fan1=|fan2=|chain_acs1=|chain_acs2=|chain_acs3=|chain_acs4=|chain_rate1=|chain_rate2=|chain_rate3=|chain_rate4'
By using "grep" I was able to read out the real hardware values.
The next step is the customization of Bitman's web interface, so that all values can be viewed there in the future. Currently it runs slightly overclocked (587mhz). Performance currently about 15.5-17.7 ksols. Stable!
I will contact you again with new results.
Let it all go well.
Happy Mining to YOU all!
Greets @cursedmining and "EFUDD" (https://bitcointalk.org/index.php?action=profile;u=2271429) from @bitcointalk.org thanks for your Support!!
Run Baby Run !!