I took a stab at typing the upper block of German text in the German datasheet into Google translate by hand - not easy as I have no idea how to get German accents like 'umlaut' or the unique double-S character on my British keyboard.
This is how it seems to go, apologies to any German readers if any of this is hilariously wrong.
Quote:
-Programming for all Bipolar PROMs.
-Manufacturer sets all memory cells to 'H'.
-Connect power to Vcc and ground.
-Apply the address of the word to be programmed to the address bus, allow the address to stabilise.
-Selection of the circuit is by deactivating with CS, H at CS1 or CS2.
-Apply programming pulse (+ 21V) to the corresponding output; leave the others open or take them H. Only one bit at a time may be programmed.
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In other words, all bits in all locations have a default state of high, the aim of the programming process is to set any bits which need to be set low, low.
The chip select part sounds a bit strange but suggests the chip should be un- selected during the programming process by taking either of the CS pins high.
If (for a given word) you want a bit to be low, then (with the address pins stable) you apply a 21V programming pulse to the corresponding data bit pin, leaving the others open or pulling them high. Repeat for any other bits required to be low within that address, then move to the next address. You can't apply +21V to several data pins at once, each bit has to be done individually.