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I spent a couple of hours searching on internet and these are my conclusions (I hope): Lcd dot matrix: 120dot H x 64dot V. Lines are connected to 5238 output. As 5238 have only 32 output, I think it drives 2 lines at time (probably it is connected to the common of each line): probably line 1 with 33, 2 with 34 and so on. Three 5839 are series connected to form a 120bit shift register to drive an entire line (for the upper half of the display (IC1, IC2 and IC3), and the others for the lower half (IC4, IC5 and IC6).
I have downloaded (from www.oki-europe.de) data sheets for these ICs and the pinout of LCM is this (my multimeter helped me...) 01 - DataIn 5839 lower half (lines 33..64) 02 - DataIn 5238 03 - DF 5238 + 5839 (all ics) 04 - Clock 5238 connected to LOAD 5839 (line advance for 5238 and latch data in 5839) 05 - Clock 5839 (all ics) 06 - DataIn 5839 display upper half (lines 1..32) 07 - VDD Vdd 5238 and Vdd 5839 08 - GND Vss 5238 and Vss 5839 09 - VEE Negative supply for display (*) 10 - Vctrl Reference voltage for contrast regolation (*)
(*) There is a little transistor (PNP) and Base is connected to pin 10, collector to pin 09 and emitter to all ICs Vee pin.
I think we must shift a 1 (with all 0) in 5238 to enable one line at time. In the meanwhile, we must shift the 120 bit of the next line into the two chains of 5839 preparing the NEXT line. When the two lines are loaded, a pulse on pin 4 must advance the 1 in 5238 and load the two lines into the output latches of 5839. And so on.....
I suppose this is a possible scenario and I'll try to test it as soon as possible. I haven't so many free time to spend with these things I like. If you are interested in, I'll send you an e-mail when I have news.
Ciao Fabio