Voice Playback CHIP SD20

[robert.quaas]

Hi Darrel

Thanks for help of this. I finally got it working, the engineer from the manufacturer found a small bug in their chip firmware. So anyone interested in using this chip should increase the reset time and increase the time for playback also.


See the amended code here :

@ DEVICE XT_OSC,MCLR_OFF,LVP_OFF,WDT_OFF,PROTECT_OFF

DEFINE LOADER_USED 1

' ** Setup the Resonator Frequency, in Mhz **
Define OSC 4

Baud con 84 ' 9600 baud rate

' ** Port configurations **
TX VAR PORTB.5
RX VAR PORTB.2
CLK VAR PORTA.4
DI Var PORTA.0
RESET VAR PORTB.6
PIEZO VAR PORTB.7

DAT VAR WORD
Idx VAR BYTE

counter var byte
volume var word

volume = 65527

'---------------------------------------------------------------------------

Init:
ANSEL = 0 'Configure all pins to digital operation since not using ADC
CMCON = 7 ' disable comparators

begin:
low piezo

dat = $FFF7
serout2 tx,baud,["Voice Volume - 1st Data = ",bin16 dat,13,10]
GOSUB SendDat

dat = $4
' set counter to file no. 4
counter = 4
serout2 tx,baud,["Address 4 of voice file - 2nd Data = ",bin16 dat,13,10]
GOSUB SendDat

playaddr:
dat = $fffe
serout2 tx,baud,["Play/Pause - 3rd Data = ",bin16 dat,13,10]
' GOSUB SendDat
GOSUB Playdata

' --------------------------------------------------------------------------
switch:

'if porta.2=0 then
' counter = counter - 1
' if counter<=1 then counter = 2
' dat = counter
'
' serout2 tx,baud,["Address of voice file - 2nd Data = ",bin16 dat,13,10]
' GOSUB SendDat
' goto playaddr
'endif

if porta.1=0 then
counter = counter + 1
if counter>=7 then counter = 6
dat = counter

serout2 tx,baud,["Address of voice file - 2nd Data = ",bin16 dat,13,10]
GOSUB SendDat
goto playaddr
endif

' Reduce Volume
if porta.2=0 then
volume = volume - 1
if volume<=65520 then volume = 65527
dat = volume

serout2 tx,baud,["Address of voice volume = ",bin16 dat,13,10]
GOSUB SendDat
'goto playaddr
endif

goto switch

STOP

'---------------------------------------------------------------------------

SendDAT:
LOW RESET ; 5ms reset pulse
PAUSE 5
INPUT RESET
PAUSE 300 ; 300ms before data

For Idx = 15 to 0 STEP -1 ; loop thru the bits
LOW CLK ; set CLK LOW
IF dat.0(Idx) THEN
INPUT DI ; if bit = 1 then INPUT, not HIGH
ELSE
LOW DI ; if bit = 0 then LOW
ENDIF
PAUSE 1 ; data settle time
INPUT CLK ; clks data on rising edge
PAUSE 1 ; data read time
NEXT Idx ; do rest of the bits
INPUT DI ; leave data line tri-stated
RETURN


' --------------------------------------------------------------------------

Playdata:

LOW RESET ; 5ms reset pulse
PAUSE 5
INPUT RESET
PAUSE 1250 ; 300ms before data


For Idx = 15 to 0 STEP -1 ; loop thru the bits
LOW CLK ; set CLK LOW
IF dat.0(Idx) THEN
INPUT DI ; if bit = 1 then INPUT, not HIGH
ELSE
LOW DI ; if bit = 0 then LOW
ENDIF
PAUSE 1 ; data settle time
INPUT CLK ; clks data on rising edge
PAUSE 1 ; data read time
NEXT Idx ; do rest of the bits
INPUT DI ; leave data line tri-stated
RETURN

' --------------------------------------------------------------------------

All the best; Happy NEW Year !!!

[Darrel Taylor]

Wow, you have to wait 1-1/4 seconds after the reset.

That's quite a "Bug".

Especially since the datasheet says ...

1 second after reset , if no action to the module, the chip will be into standby status within one second if no action after reset.

Well, at least it works!

Happy NEW YEAR!

[robert.quaas]

Thanks Darrel for your help.

All the best and Happy New Year

Robert Quaas