On 24/08/2019 16:18, N_Cook wrote:
Decoding so far, for anyone else doing similar (J makes an ideal search
engine term along with SZYCLCD.COM and ident YGFB178004-A1). 12MHz
sampling and 20 M samples per run on the analyser with d0 line for
trigger. SPI protocol with d3 as clock,d0 as MISO, d4 as MOSI, 4 bit
word length so superfluous analyser 8bit zeros removed in the following.
d1 and d2 only active during power-up page , not in measure mode.
For clarity and reduction, repeats in the coding via the following
look-up table.

J=
4,F,D,8,8,D,D,4,1,E,8,C,6,0,C,2,A,0,2,0,5,0,9,2,C, B,1,1,1,1,1,1,1,1,6,0,7,C,8,0,0,0,

K= 3,0,0,0,0,0,0,0,0,0,0,0,0,0,
L= 2,0,0,0,4,0,7,0,8,0,0,8,
N=2,0,A,0,0,8,4,0,8,0,0,4,
P=0,0,0,0,0,0,0,0,8,0,0,0,
Q=8,A,0,0,0,8,F,0,8,0,0,C,
R=0,0,4,0,5,0,8,0,0,8,
S=1,0,0,8,4,0,8,0,0,4,
T=1,0,0,8,F,0,8,0,0,C,
U=0,0,0,0,0,0,

Assuming J is invariant for this make and model in question, about 20
readings so far in the 1.000 to 2.000 display range ,it is invariant,
L to U would contain variation for units ,hundreds and thousands, DPs
and nulls and probably annunciators and other display rows data for the
other 3 lines in the display.

Single example of coding for the reading 1.264 in the bottom line for
the frames sent on pressing "measure" , running the analyser after
power-up each time and d0 line trigger occuring after pressing "measure"
, second frame is repeat of the first, powering down the measurer after
each reading.
1.264
J,K
L,K
N,K
Q,K
P,K
2,D,R,K
6,B,S,K
C,E,T,K
8,7,U,
J,K
2,D,R,K
6,B,S,K
C,E,T,K
8,7,U,

Preliminary decoding for readings in the range 1.0.. to 1.7..
for tenths in the rank P,K,*,x,R,K,*.y,S,K after the primary ident J,
where * is don't care/ignored and x,y is the coding
2 on the LCD codes to (x,y) D,B in the SPI
3 ~ D,7
5 ~ D,5
6 ~ D,D
7~ 9,7

for hundredths,
only *.*5* and *.*6* measures in the display so far
in the rank T,K,*,x,U
5 ~ SPI F
6 ~ 7
will probably require 1 or 2 other elements for the full set 0 to 9

for thousandths (for eventual use thousandths [mm] would be redundent)
R,K,x,*,S,K,y,*,T,K,z,*U
x, y, z SPI
1~ 6, 4, 0
2~ A, C, 4
3~ 6, C, 4
4~ 6, C, 8
6~ E, 8, C
7~ 6, 4, 4
8~ E, C, C


I might hookup an Arduino or a Pi , as in the intended usage , rather
than analyser ,for easier taking of pairs of readings/ LCD display
decoding look-up table determination , for the full set. There may be
transcription errors in the above of course.

For units decodng

From the previous, for unit=1 eg 1.264
R=0,0,4,0,5,0,8,0,0,8,
S=1,0,0,8,4,0,8,0,0,4,
T=1,0,0,8,F,0,8,0,0,C,

unit is more simply represented by the first term of each of R,S and T
string and so preliminary look-up table
unit ~ SPI R(1) , S (1) , T(1)
1~ 0,1,1
2~ 3,2,1
5~ 1,3,2
6~ 3,3,2
8~ 3,3,3
9~ 1,3,3
10~ 3,5,7 (or maybe 0) , (plus 3,4 and 7 also unknown so far)
and the remaining 9 terms of R,S and T are invariant for the readings
taken so far.

When the sun goes down a bit, I'll try some pairings in the range 10 to
50 metres, for 10s decoding

--
Monthly public talks on science topics, Hampshire , England
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