PIC plus-5110 LCD-GPS-BMP280-HMC5983

[camerart]

Hi C,
Downloaded, will try tomorrow.
E

Hi E,
If the image attached is ok, then it is working. I needed to comment out all of the SPI section, for SIM.
Thanks.
C.

 

[ericgibbs]

hi C,
I would move the SPIPrepare outside the main loop. say just before the start label.
There is one point which is bugging me, does the LONG need to be right shifted 4 times, as p_xlsb is always zero.
Read the d/s and let me know
E
SPIPrepare
start:

'do a lcd Reset
Gosub rst_lcd '5110 states very early RESET is important

'''''''Gosub cmd5110 'init lcd temp rem out
WaitMs 10
Call clear()
'@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
'simulated BMP Regs values
p_xlsb = 0x40 'low byte
p_lsb = 0xe2
p_msb = 0x01 'high byte
p_xlsbnlsb = 0x00
'@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@

main:
'###################################################################
''' Gosub get_neo 'Reads NMEA DATA temp rem out
PORTD.4 = 1 'CHIP SELECT 5110 OFF
WaitMs 100 'Does CS need time to switch? [SHORTEN OR REMOVE THIS LINE]
PORTD.5 = 0 'CHIP SELECT [hpa] ON

Goto test1 ''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''

SPICSOn
SPISend 0xf4 'Control reg addr
SPISend 0x03 'Normal mode
SPISend r_p_xlsb 'READ ADDR PRESSURE xlsb from BMP280
SPIReceive p_xlsb 'Least sig BYTE
SPISend r_p_lsb 'READ ADDR PRESSURE lsb from BMP280 MID
SPIReceive p_lsb 'mid sig Byte
SPISend r_p_msb 'READ ADDR PRESSURE msb from BMP280 MOST
SPIReceive p_msb 'Most sig BYTE
SPICSOff
PORTD.5 = 1 'CHIP SELECT OFF[hpa][SPI]

test1:
'dummy values from SP reads ''''''''''''''''''''''''''''''''''''''''''''''''''
p_xlsb = 0x40 '''' NOTE: low nibble always zero
p_lsb = 0x23
p_msb = 0x01
''' is 74560 as decimal

'Join all PRESS bytes as long
p_xlsbnlsb.LB = p_xlsb
p_xlsbnlsb.HB = p_lsb
p_msbnlsbnxlsb.LW = p_xlsbnlsb
p_msbnlsbnxlsb.HW = p_msb

'ASCII serial out of Bytes,Word or Single
Hserout "BMP LONG Value=", #p_msbnlsbnxlsb, CrLf

msg1 = #p_msbnlsbnxlsb
Hserout "BMP as ASCII=", msg1, CrLf, CrLf

 

[camerart]

Hi E,
As expected
EDIT: Unimportant: I moved all of the XLSB to the right [p_lsbnxlsb.HB] in the variables.
C

 

[ericgibbs]

hi C,
I suspect you may have to shift all the value right by 4.??
If so a simple edit.
image shows before and after shift
E
'ASCII serial out of Bytes,Word or Single
Hserout "BMP LONG Value=", #p_msbnlsbnxlsb, CrLf

msg1 = #p_msbnlsbnxlsb
Hserout "BMP as ASCII=", msg1, CrLf, CrLf

p_msbnlsbnxlsb = ShiftRight(p_msbnlsbnxlsb, 4)

'ASCII serial out of Bytes,Word or Single
Hserout "BMP LONG Value=", #p_msbnlsbnxlsb, CrLf

msg1 = #p_msbnlsbnxlsb
Hserout "BMP as ASCII=", msg1, CrLf, CrLf

 

[camerart]

Hi E,
Working in SIM, now shows values=74560 and 4660.

Would you expect this to work with the 5110? The 5110 doesn't start!
C

 

[ericgibbs]

hi C,
Ensure that the 5110 is initialised.
Have been looking at the BMP d/s, look at this image etc.
E

test1:
'test values from Datasheet
''0x7EED0 [ 20 bit left shifted 4] = 519888 decimal
''''''''''''''''''''''''''''''''''''''''''''''''''
p_xlsb = 0xd0 '''' NOTE: low nibble always zero
p_lsb = 0xee
p_msb = 0x07

'Join all PRESS bytes as long
p_xlsbnlsb.LB = p_xlsb
p_xlsbnlsb.HB = p_lsb
p_msbnlsbnxlsb.LW = p_xlsbnlsb
p_msbnlsbnxlsb.HW = p_msb

'ascii serial out of bytes,Word Or Single
Hserout "UnShifted BMP LONG Value=", #p_msbnlsbnxlsb, CrLf
msg1 = #p_msbnlsbnxlsb

Hserout "BMP as ASCII=", msg1, CrLf, CrLf

p_msbnlsbnxlsb = ShiftRight(p_msbnlsbnxlsb, 4)

'ascii serial out of bytes,Word Or Single
Hserout "Shifted BMP LONG Value=", #p_msbnlsbnxlsb, CrLf
msg1 = #p_msbnlsbnxlsb
Hserout "BMP as ASCII=", msg1, CrLf, CrLf

 

[ericgibbs]

hi C,
Have you seen the corrective maths calculations required to get a pressure value in Pa.???

 

[camerart]

Hi E,
Got the 5110 going after 'initialisation'
Using the BMP280 for reading, should I get anything at 'ALT='? At the moment, it starts with '1372' and quickly changes to '524288' and doesn't change even when at altitude (up stairs)
I would like to see the 'ALT=' result change, before looking at the calculation to hPa, we may not need it, if we use < and >. For now anyway.
C.

 

[ericgibbs]

hi C.
The 524288 is the test value from the d/s.
Use the SPI read values and Rem out the test values.
E

 

[camerart]

hi C.
The 524288 is the test value from the d/s.
Use the SPI read values and Rem out the test values.
E

Hi E,
This wa READ using SPI with the test values remmed out. I'll double check that the READ settings are correct.
C.

 

[ericgibbs]

hi C,
May I ask, how do you intend using the Barometric pressure value in your project.?
E

 

[camerart]

Hi E,
First I would like to see the P_number rising and lowering, so as I can get a feel for it, in the simplest way possible.
Next I would add a Compass module in a similar fashion.
Then try to translate the readings to PWM used in RC control.
Then put it in a Tricopter and have it hovering a set height off the ground aiming a particular direction.
Once all that is done, I hope to refine it, each section at a time.
There are lots of details to refine, and for me, it would be 'perhaps' a waste of time to do it all during the module testing stage.
An exmple of this is: Altitude readings change with the temperature, and the BMP280 has a 'Temp' reading to add into any calculation, but for this project I can't tell till if it's needed till it's flown.
C.

 

[ericgibbs]

hi C,
Barometric pressure changes due to the weather pattern.
Unless you have fixed Base station measuring ambient pressure as a correction factor, how will you calculate the Alt of the model?
E

 

[camerart]

hi C,
Barometric pressure changes due to the weather pattern.
Unless you have fixed Base station measuring ambient pressure as a correction factor, how will you calculate the Alt of the model?
E

Hi E,
True.
I would place the module on the ground press a button, and take the reading then compare height readings from the first one. A test for 1Mtr 2Mtr etc will give numbers, then I'll see what's needed as I go along. I hope to be able to fly by eye, so for now interpretation calulations, may not be necessary.
C.

 

[camerart]

Hi,
[ON PCB, not SIM] I've tried WRITEing to one of the 'P' registers and the '#p_msbnlsbnxlsb' result changes, so it appears that it is set up correctly, but as soon as I don't WRITE, and only READ, I only get the ALT=524288 READing.
SEE: The lines with !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
C.
'#########################################################################
Const r_p_xlsb = 0xf9 'READ ADDR PRESSURE xlsb from BMP280 LEAST
Const w_p_xlsb = 0x77 'WRITE ADDR PRESSURE xlsb from BMP280 LEAST
Dim p_wxlsb As Byte '!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
p_wxlsb = 0 '!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
Const r_p_lsb = 0xf8 'READ ADDR PRESSURE lsb from BMP280 MID
Const r_p_msb = 0xf7 'READ ADDR PRESSURE msb from BMP280 MOST
'##########################################################################
Disable High
Disable Low
Include "fontsml.bas" 'This 'FONT' file nust be in the same folder as this program code
msg1 = ""
Hseropen 9600
Hserout "Ready!", CrLf
SPIPrepare
start:
'do a lcd Reset
Gosub rst_lcd '5110 states very early RESET is important
SPIPrepare
Gosub cmd5110 'init lcd<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<
WaitMs 10
Call clear()
'@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
'simulated bmp regs values
''p_xlsb = 0x40 'low byte
''p_lsb = 0xe2
''p_msb = 0x01 'high byte
''p_lsbnxlsb = 0x00
'@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@

main:
'###################################################################
Gosub get_neo 'Reads NMEA DATA<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<
PORTD.4 = 1 'CHIP SELECT 5110 OFF
WaitMs 100 'Does CS need time to switch? [SHORTEN OR REMOVE THIS LINE]
PORTD.5 = 0 'CHIP SELECT [hpa] ON
WaitMs 100
''Goto test1 ''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
SPICSOn
SPISend 0xf4 'Control reg addr
SPISend 0x00 '3 'Normal mode
'******************************************************************
'SPISend w_p_xlsb 'READ ADDR PRESSURE xlsb from BMP280!!!!!!!!!!!!!!!!!!!!!!!!!
'SPISend p_wxlsb 'Least sig BYTE!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
'*********************************************************************
SPISend r_p_xlsb 'READ ADDR PRESSURE xlsb from BMP280
SPIReceive p_xlsb 'Least sig BYTE>>>>>>>>>>>>>TEST<<<<<<<<<<<<<<<<<
SPISend r_p_lsb 'READ ADDR PRESSURE lsb from BMP280 MID
SPIReceive p_lsb 'mid sig Byte
SPISend r_p_msb 'READ ADDR PRESSURE msb from BMP280 MOST
SPIReceive p_msb 'Most sig BYTE
SPICSOff
WaitMs 500
PORTD.5 = 1 'CHIP SELECT OFF[hpa][SPI]

 

[ericgibbs]

hi C,
Visually comparing the value you read and the example value in the d/s, they are very close, it may be working.??

You have to do the maths in #327 in order to get a actual Pa value.

E

 

[camerart]

hi C,
Visually comparing the value you read and the example value in the d/s, they are very close, it may be working.??

You have to do the maths in #327 in order to get a actual Pa value.

E

Hi E,
I accept that for a Pa value or an altitude in Mtrs, would need a calculation, also the reading needs compensation from other aspects, but I would have though before that I should be able to READ the pressure register addresses and get readings that move as I raise the module. This is what I'm trying to do first.
What I tried was to WRITE to one of the register addresses and it shows a difference other than 524288, but when I try to get the module to output actual DATA it always shows 524288.
C.

 

[camerart]

Hi,
I'm just looking at the control register 0xF4. Here the MODE and sampling settings for TEMP and PRESS are set. I've tried setting it to 0x1F which I think enables PRESS and sets the sample rate high, with the TEMP diasbled and the MODE setting to Normal.
I get a reading of 550720.
C.

 

[ericgibbs]

hi C,
Have you tried converting readings from the BMP280 to Pa.?
For ref only, this is the fiddling I had to do with Oshonsoft when I used the BMP180.
It is a I2C reading method.
E

rd_pressure:
I2CWrite sda, scl, 0xee, 0xf4, 0x34
WaitMs 5
I2CRead sda, scl, 0xef, 0xf6, ph, pm, pl
presraw = ph * 256 + pm

'cal the pressure
b6 = b5 - 4000
b62 = b6 * b6 / 4096

x1 = (b2 * b62) / 4096
x2 = ac2s * b6 / 2048
x3 = x1 + x2

b3 = ((ac1 * 4 + x3) + 2) / 4

x1 = ac3s * b6 / 8192
x2 = (b1 * b62) / 65536
x3 = ((x1 + x2) + 2) / 4

b4 = ac4 * (x3 + 32768) / 32768
b7 = (presraw - b3) * 50000
pp = (b7 / b4) * 2
''pp = (b7 * 2) / 4
x1 = (pp / 256) * (pp / 256)
x1 = (x1 * 3038) / 66536
x2 = (-7357 * pp) / 65536

pps = pp + (x1 + x2 + 3791) / 16
pps = pps / 10
b2aval = pps
Gosub bin2asc
Lcdcmdout LcdLine3Home
Lcdout "P1 ", ascbfr4, ascbfr3, ascbfr2, ascbfr1, ".", ascbfr0, "mb"
Hserout "P1 ", ascbfr4, ascbfr3, ascbfr2, ascbfr1, ".", ascbfr0, "mb", CrLf
Hserout CrLf
Return

 

[camerart]

Hi E,
Blimey!
I try my hardest to have the simplest programs, that I can get away with, as something like that would overwhelm me.
So far, I haven't got any readings to convert to anything yet
I'll remember where your conversion is for when I do need it though, thanks.
C