diskboot parameters (lba48 for secondary IDE)

Hello,

This setting of lba48 parameter works for Primary Master
[pri=10o] PATH=/proc/boot diskboot -b1 -D1 -odevc-con,-n4 -o"devb-eide, eide master=lba48"
This setting works for Primary Master and Primary Slave
[pri=10o] PATH=/proc/boot diskboot -b1 -D1 -odevc-con,-n4 -o"devb-eide, eide master=lba48,slave=lba48"

Question:

How can I change parameteres for working lba48 on Secondary IDE channel.?

Thanks
David