Need Debug Help
Kirk Fraser
Posts: 364
I'm trying to get a fairly simple Spin program to work. The current goal is to read upto 6 pots from a MCP3208 and display the value 0-4095. The problem is the values always stay at either 0 or 4095, nothing in between when I rotate a pot and no change when I remove the pot from the MCP3208 input.
The object which drives the MCP3208.differs from those found on Obex but I don't suspect it. I think it's possibly my MCP3208 has gone bad or some other hardware problem. But I don't know. I have the chip in a socket so maybe I should buy a new one and swap it? The hardware has been sitting around so it may have gotten a static shock, but the Propeller chip is working. Suggestions? Thank you.
Here's the object which drives the MCP3208. This may be needed to show how it returns the pot values to be read by the main program. Perhaps I have some bug in my variable definition or use or something?
.
obj
' pwmA : "jm_lfpwm_8x" ' A pwm output
' pwmB : "jm_lfpwm_8x" ' B pwm output
adc : "jm_mcp3208_se_fast" ' Pot multiplex input
dbug : "FullDuplexSerial" ' pc serial IO
var
long pot[8]
long pot1
long pot2
long pot3
long pot4
long pot5
long pot6
byte dir ' adc channels
con
_clkmode = xtal1 + pll16x
' _xinfreq = 6_000_000 ' use 6MHz crystal
_xinfreq = 6_250_000 ' use 6.25MHz crystal
CLK_FREQ = ((_clkmode - xtal1) >> 6) * _xinfreq
clk = 20
cs = 21
dio = 22 'adc SPI buss
ca = 15 'coil 8a
cb = 14
ch = 8 'channel for pot in
cls = 14
PUB main
{{Start objects}}
adc.start(cs, clk, dio, @pot[0]) ' start ADC driver
pwma.start(1, ca, 100) ' start PWM drivers
pwmb.start(1, cb, 100)
' dbug.start(rxpin, txpin, mode, baudrate)
dbug.start(31, 30, 0, 115200) ' start debug object
waitcnt(clkfreq*3+cnt) ' For Debug Startup
dbug.tx(cls)
{{Run Loop}}
repeat
readPots ' read adc values
' pwma.set(ch-1, pot2 / 4)
' pwmb.set(ch-1, pot3 / 4)
pub readPots
dbug.str(string(13))
pot1 := pot[1 - 1]
dbug.str(string(" pot1 "))
dbug.dec(pot1)
pot2 := pot[2 - 1]
dbug.str(string(" pot2 "))
dbug.dec(pot2)
pot3 := pot[3 - 1]
dbug.str(string(" pot3 "))
dbug.dec(pot3)
pot4 := pot[4 - 1]
dbug.str(string(" pot4 "))
dbug.dec(pot4)
pot5 := pot[5 - 1]
dbug.str(string(" pot5 "))
dbug.dec(pot5)
pot6 := pot[6 - 1]
dbug.str(string(" pot6 "))
dbug.dec(pot6)
The object which drives the MCP3208.differs from those found on Obex but I don't suspect it. I think it's possibly my MCP3208 has gone bad or some other hardware problem. But I don't know. I have the chip in a socket so maybe I should buy a new one and swap it? The hardware has been sitting around so it may have gotten a static shock, but the Propeller chip is working. Suggestions? Thank you.
Here's the object which drives the MCP3208. This may be needed to show how it returns the pot values to be read by the main program. Perhaps I have some bug in my variable definition or use or something?
.
'' =================================================================================================
''
'' File....... jm_mcp3208_se_fast.spin
'' Purpose.... for MCP3208 -- single ended mode, runs automously
'' Author..... Jon "JonnyMac" McPhalen
'' Copyright (c) 2010-2011 Jon McPhalen
'' -- see below for terms of use
'' E-mail..... jon@jonmcphalen.com
'' Started....
'' Updated.... 18 SEP 2011
''
'' =================================================================================================
{{
VDD (2.7 to 5.0)
MCP3208 
┌─────────────────┐ │
ch0 ────┤1 CH0 VDD 16├──┫
ch1 ────┤2 CH1 VREF 15├──┘
ch2 ────┤3 CH2 AGND 14├──┐
ch3 ────┤4 CH3 CLK 13├──│──────── clk
ch4 ────┤5 CH4 DOUT 12├──│──┐ 3k3
ch5 ────┤6 CH5 DIN 11├──│────┻── dio
ch6 ────┤7 CH6 /CS 10├──│──────── cs
ch7 ────┤8 CH7 DGND 9├──┫
└─────────────────┘ │

}}
con
BIT_US = 2 ' bit timing ~us
FRAME_MS = 1 ' frame timing in millseconds
var
long cog ' cog used by driver
long cspin ' chip select pin
long clkpin ' clock pin
long diopin ' data i/o pin
long pntr ' hub pntr to results
long clktime ' timing for 1/2 bit (in ticks) '
long frametime ' frame timing for hub updates
pub start(cs, clk, dio, dest) : ok
'' Starts MCP3208 measurements, single-ended mode
'' -- cs is chip select pin
'' -- clk is clock pin
'' -- dio is data io pin (di and do connnected with 3.3k resistor)
'' -- dest is hub address for values (8 longs)
stop
longmove(@cspin, @cs, 4) ' copy parameters
clktime := (clkfreq / 1_000_000 * BIT_US) >> 1 ' half bit timing
frametime := clkfreq / 1_000 * FRAME_MS ' frame (8 ch) timing
ok := cog := cognew(@entry, @cspin) + 1 ' start the cog
pub stop
'' Stops cog (if running)
if cog
cogstop(cog~ - 1)
longfill(pntr, 8, 0)
dat
org 0
entry mov tmp1, par ' start of structure
rdlong tmp2, tmp1 ' read CS pin #
mov csmask, #1
shl csmask, tmp2
or outa, csmask ' make output/high (disable)
or dira, csmask
add tmp1, #4
rdlong tmp2, tmp1 ' read CLK pin #
mov clkmask, #1
shl clkmask, tmp2
andn outa, clkmask ' make ouput/low
or dira, clkmask
add tmp1, #4
rdlong tmp2, tmp1 ' read DIO pin #
mov diomask, #1
shl diomask, tmp2
add tmp1, #4
rdlong adcpntr, tmp1 ' read hub address of output array
add tmp1, #4
rdlong clktix, tmp1 ' read cnt ticks for half bit
add tmp1, #4
rdlong frametix, tmp1 ' read cnt ticks per 8-ch frame
mov chan, #0 ' initialize channel channel
mov frmtimer, cnt
add frmtimer, frametix ' set frame (8 channels) timing
adcmain andn outa, csmask ' activate adc
or dira, diomask ' make dio an output
muxout mov muxbits, #%1_1000 ' set for single-ended
add muxbits, chan ' add channel
mov count, #5 ' send 5 bits
:loop test muxbits, #%1_0000 wc ' move bit4 to C
muxc outa, diomask
call #bitdelay ' let dio settle
call #clockbit ' clock the bit out
shl muxbits, #1
djnz count, #:loop
adcin andn dira, diomask ' make dio an input
mov level, #0 ' clear workspace
mov count, #13 ' null + 12 data bits
:loop call #clockbit ' clock the bit in
call #bitdelay ' let dio settle
shl level, #1 ' prep for new bit
test diomask, ina wc ' get new bit in C
muxc level, #1 ' move to bit0
djnz count, #:loop
or outa, csmask ' deselect
call #bitdelay
mov tmp1, adcpntr ' point to hub array
mov tmp2, chan ' channel index
shl tmp2, #2 ' adjust for longs
add tmp1, tmp2 ' point to array[chan] in hub
and level, HX_FFF ' cleanup reading
wrlong level, tmp1 ' write to hub
add chan, #1 ' next channel
and chan, #%111 wz ' rolloever if required
if_z waitcnt frmtimer, frametix ' wait for end of frame if done
jmp #adcmain
clockbit or outa, clkmask ' CLK high
call #bitdelay
andn outa, clkmask ' CLK low
clockbit_ret ret
bitdelay mov clktimer, cnt ' start timer
add clktimer, clktix ' set for 1/2 bit tix
waitcnt clktimer, #0 ' wait for expiration
bitdelay_ret ret
' --------------------------------------------------------------------------------------------------
HX_FFF long $0FFF ' mask for 12 bits
csmask res 1
clkmask res 1
diomask res 1
clktix res 1
frametix res 1
adcpntr res 1
chan res 1
muxbits res 1
count res 1
level res 1
frmtimer res 1
clktimer res 1
tmp1 res 1 ' work vars
tmp2 res 1
fit
dat
{{
Terms of Use: MIT License
Permission is hereby granted, free of charge, to any person obtaining a copy of this
software and associated documentation files (the "Software"), to deal in the Software
without restriction, including without limitation the rights to use, copy, modify,
merge, publish, distribute, sublicense, and/or sell copies of the Software, and to
permit persons to whom the Software is furnished to do so, subject to the following
conditions:
The above copyright notice and this permission notice shall be included in all copies
or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF
CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE
OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
}}
Comments
pub LSADC &04.02.03.01 !ADC 8 0 DO CR I .BYTE ." : " I ADC@ DUP .DEC SPACE 5 SHR 1+ FOR "*" EMIT NEXT LOOP ;and run it like this:
LSADC
00: 0000 *
01: 0000 *
02: 0000 *
03: 0000 *
04: 0000 *
05: 0000 *
06: 0000 *
07: 0000 * ok
looks like your pins are different