Go to this site and download Easydownloader version 4 or above.
http://www.kmitl.ac.th/~kswichit/
Go to 2051 section.
programmer has just same 2051 and one '273 latch.
Better use '573 type which has neat arrangement
for handwiring. Total cost to me was less than $2.
It has also section for 8085, Z80 etc so can visit
the memories of commandor 64 !!
I want to tell someother person who has asked for
cost of I2C LCDs. The 2wire LCD interface doesnt need
that types. You only need to have 50cent serial shifter
and or two if you dont want the gimmic in the circuit
of DTL logic. Gives out clean 8data lines + 2-3 control
lines. Saves uC of lots lines too!