To convert a stock 1050 drive into a US Doubler SD/DD drive.

Parts needed:

        1 - 6810P ram
        1 - 2732A EPROM (blank or already burnt with code)
        1 - code for new EPROM (either Intel HEX file or BIN file)

Cost:  $1.19 for 6810P RAM and $5.65 for 2732A EPROM.

Note:  The code for the USD ROM is copyright ICD and I guess now
       also FTE.  To use this code, you should already have at least
       one copy of the US Doubler package and should only use this
       information to make a replacement for that original package.

Bend out pins 10 and 14 on one 6810P.
Place both 6810P's together, upper 6810P has pins 10 & 14 bent out.
Solder all other pins together except pins 10 and 14 of top 6810P.
Jumper pin 10 of upper 6810P to pin 14 of lower 6810P.
Jumper pin 12 of upper 6810P to pin 14 of upper 6810P.
Replace stacked 6810P's in socket.
Replace U10 rom with new 2732A eprom, checksum 97D6.

That's it.

Works fine with SpartaDOS 3.x and SpartaDOS X 4.2.x in turbo mode.