Firstly for anyone else playing with these neat cheap laser diode measuring devices. I'm initially playing with a (Lidl) Parkside PLEM 50 (50m range), to eventually use a Lomvum LV 120 (120m range) coupled to a pc via Pi/Arduino. Both have 4 line 7segment LCD plus annunciators display with a "chip on glass" look-up page chip for decoding and driving the LCD. Made by SZYCLCD.COM and ident YGFB178004-A1 on the .5mm spacing ribbon and I know by swapping between each, they are compatible between both devices , completely different external and internal appearance, but same STM micro. 14 way ribbon to LCD , 2 w for backlight, 2w for power to chip on glass and a number of apparently inactive lines in measurement mode anyway . So d0 clock , d3 and d4 used for SPI update principal lastline of LCD and d2 +d3 active during power-up/first page but not in measure mode. Breaking-out at the ZIF ribbon socket and using Hobbycomponents "matchbox" pulse analyser and Sigrok/Pulseview and pairs of readings on the lower line of the LCD, ie switch unit on, then just pressing "measure" once initiates the SPI clock pulses. The LCD is updated from switch-on display in 0.5 to 1 seconds , so the data must be contained within the first 2 or 3 frames of data. Short duration bursts of clock then various amounts of dead space , as much as 400mS between frames, highly variable duration. I was hoping the same as
429-1961499 : 0C
980976-981002 : 0D 981001-981026 : 00 981026-981051 : 04how to tidy up word apportionment ?.
And then for pairs of metre/mm distance readings I cannot get any sense of pertinent words to decode/look-up (redundant 0's removed here for linwrap) and only frames 2 and 3 including the "smears" B1820 sequence looked promising as an ident but non appearance in one dataset.
00012080049008B180208010400A200 =6.345a 8B18020400108A000001208004900 =6.345b8B180200010400A4000044041002101 =5.085a
000120A000504CD0401048082004202 =5.085b (B18020 sequence not appearing in any succeeding frame, well beyond 1 second)00012080049088B180208010400A404 =1.564a B180200010400A400008010400A404 =1.564b