VDI-RODERICO

[roderico]

can someone upload code for ks0107 lcd?

it might work with the "_B" version, or else it would be better if you could post or link the datasheet of your display to see if it is compatible...

[roderico]

VDI 2.0

after many tests (mainly by kroman01) this is version 2.0. I updated the schematics adapting kroman01's mod for channel Y and adjusted the values of C1, C2, C3, C4, R3, R4, R5, R6, R7, R8 as an example for 2-7Hz, i.e. around 5Hz, it might need additional testing, but in any case the firmware is also compatible with previous schematics.

R7, R8: 1%
SW4: optional
Y1, C12, C13: only if PIC does not have a 4MHz internal oscillator
R11: depends on the display and it needs to be adjusted for low current (e.g. 20 mA or less)
R15: only if using a LCD display (VEE, CS1, CS2, RST are not used)

the firmwares were built with Microchip XC8 demo compiler, binary files ending with "_B" are for GLCDs with CS1 and CS2 without a bar like kroman01's GLCD and the others for GLCDs with a bar in CS1 and CS2. I also included the firmware for PIC18F252 as an example of an old PIC that needs an external oscillator.

[roderico]

you might give P18F25K22_kroman01 a try (post#19 ...

[saba]

can someone upload code for ks0107 lcd?

[roderico]

ok no problem, I will compile the two variants for version 2 since probably there are other ks0108 based displays like that one

[kroman01]

P18F25K22_kroman01 works with RA8808 lcd controller
thanks a lot, I have a few lcd to use

[roderico]

ok that would be very good, you can also give a try to the firmware I posted previously without using the 74HC14 since the change in the code is very small...

[kroman01]

it's hard to say, both versions are stable, I have to do many tests and I can change C1 and C3 to 2.2uF
as for my LCD display, I negated CS1 and CS2 using 74HC14 and the display worked properly

[roderico]

very nice video, did you notice any improvement with respect to previous version? is it more or less stable? from your video I see that the frequency of the signals goes down up to ~ 2Hz, if there was a clear improvement then the values of those resistors and capacitors might need to be changed for 2-7Hz while keeping the same gain.

Do you have the datasheet of your LCD, if the problem is only to negate CS1 and CS2 the change would not be difficult, try with this one:

[kroman01]

video from test C1 I C3 1uF values of elements R3 R4 R5 R6 C2 and C4 as shown in the diagram

https://youtu.be/HocSdTldQQo

i solved the RA8808 glcd problem ... the chip select / CS and / CS2 inputs must be negated

[roderico]

ok no problem, you would need to keep the values of R3, R5, R4, R6, C2 and C4 for testing the bandpass 3.4-7.2Hz or else we would have a different range of frequencies...

[kroman01]

there is no real reason to add additional resistors, the system will work with these two solutions, I still need to design a PCB compatible with the display for direct connection,
i have not tested with C1 and C3 1uF, there is not enough time

[roderico]

I tried kroman01's mod and it fixes the problem, there is no more clipping in Y channel, however I just moved RT2 and R9 before U1 keeping the original values and it is working fine for me, what is the reason to add additional resistors?

[roderico]

ok very good

[kroman01]

the X Y signal from IDX comes from the outputs of the amplifiers
i will do a test by changing C1 and C3 to 1uF