TRIS setting for the DS1302

[Dennis]

Hi all

I have been battling for over a week now trying to get the DS1302 clock chip working.

I think I finally have the format and code sorted , only problem is that my clock never ticks :-( in other words the time never changes!

Please could somebody either take a look at my code or advise me what I should check next.
I'm sure it is really something small or silly that I have overlooked.

Kind regards

Dennis

'device 18F4520 
'DS1302  test
'
'

'Ocsillator selections here
        OSCCON = $70            'Int CLK 8MHz
        OSCTUNE.6 = 1           'PLL 4x
        ADCON1= %00001111       '$0F = disable A/D converter
        cmcon   =   7 
        INTCON2.7 = 0     'switch pull-ups ON
'END of oscillator selections
  'timer/oscillator defines 
        DEFINE OSC 32            '4x 8MHz
'END of timer/oscillator defines
'
'
'Port IO directions and presets for port pins begin here
'TRISX = %76543210   << tris bit order numbering
'TRISA = %11111111       'All pins are outputs
'// Define port pins as inputs and outputs ...
        TRISA  = %00000000 'example only - TRISB = %00001111 ;Make B4-B7 outputs, B0-B3 inputs, 
        TRISB = %11111111  'for 4x4 keypad all input
        TRISC = %10000000
        TRISD = %00000000
        TRISE.0 = 0
        TRISE.1 = 0
        TRISE.2 = 0
'End of Port IO directions and presets for port pins begin here
'
'                   
'
'LCD defines begin here   
        DEFINE LCD_BITS 4 	'defines the number of data interface lines (4 or 8) 
        DEFINE LCD_DREG PORTD 	'defines the port where data lines are connected to
        DEFINE LCD_DBIT 4 	'defines the position of data lines for 4-bit interface (0 or 4)
        DEFINE LCD_RSREG PORTD 	'defines the port where RS line is connected to
        DEFINE LCD_RSBIT 2 	'defines the pin where RS line is connected to 
        DEFINE LCD_EREG PORTD 	'defines the port where E line is connected to 
        DEFINE LCD_EBIT 3 	'defines the pin where E line is connected 
        'DEFINE LCD_RWREG 0 	'defines the port where R/W line is connected to (set to 0 if not used)
        'DEFINE LCD_RWBIT 0 	'defines the pin where R/W line is connected to (set to 0 if not used)
        DEFINE LCD_COMMANDUS 2000 	'defines the delay after LCDOUT statement 
        DEFINE LCD_DATAUS 200 		'delay in micro seconds
'END of LCD DEFINES
'
'includes begin here
        INCLUDE "modedefs.bas"
       'end of includes
'
'HSER defines
        DEFINE HSER_RCSTA 90h ' Enable serial port & continuous receive
        DEFINE HSER_TXSTA 20h ' Enable transmit, BRGH = 0
        DEFINE HSER_SPBRG 207 ' 2400 Baud @ 32MHz, 0.17%
        DEFINE HSER_CLROERR 1 ' Clear overflow automatically
'HSER defines begin here

'-------------------------- Clock Variables ---------------------------------


'SCLK    var portC.3 ' DS1302 Clock Pin  7
'IO     var portC.4 ' DS1302 Data Pin   6
'rst     var portD.1 ' DS1302 Reset Pin 5


'pins
RST var PORTA.0 'DS1302 PIN 5
IO var PORTA.1 'DS1302 PIN 6
SCLK var PORTA.2  'DS1302 PIN 7

'variables
rtcyear var byte
rtcday var byte
rtcmonth var byte
rtcdate var byte
rtchr var byte
rtcmin var byte
rtcsec var byte
rtccontrol var byte


Main:
Low RST ' Reset DS1302 RTC
Low SCLK 'pull SCLK line LOW
' clock Set 16:45:00 04/14/08
rtcyear = $08
rtcday = $06
rtcmonth = $04
rtcdate = $14
rtchr = $16
rtcmin = $45
rtcsec = $00
Gosub SetTime   'fetch the time 
Goto loopy  'goto loopy

loopy:
Gosub gettime ' go fetch the time
Lcdout $fe, 1 'display date on top row on 16x2 lcd
lcdout hex2 rtcmonth, "/", hex2 rtcdate, "/" , hex2 rtcyear
lcdout $fe,$c0   'display time output on bottom line 16x2 lcd
lcdout hex2 rtchr, ":", hex2 rtcmin, ":", hex2 rtcsec
Pause 200 ' pause 0.2
Goto loopy  'return to main loop 




SetTime:  'this module sets the time using shiftout
RST = 1 ' bring the DS1302 RST line high and now ready for transfer

Shiftout IO, SCLK, LSBFIRST, [$8e, 0]   ' Enable write
RST = 0 ' Reset DS1302 RTC
RST = 1 ' bring reset line high and now ready for transfer
Shiftout IO, SCLK, LSBFIRST, [$be, rtcsec, rtcmin, rtchr, rtcdate, rtcmonth, rtcday, rtcyear, 0] ' Write all 8 RTC registers in burst mode
RST = 0 ' reset DS1302 RTC
Return 'return control to calling program


GetTime: ' Subroutine to read time from RTC
RST = 1 ' reset line high now ready for transfer
Shiftout IO, SCLK, LSBFIRST, [$bf] ' Read all 8 DS1302 RTC registers in burst mode using shiftout/shiftin
Shiftin IO, SCLK, LSBPRE, [rtcsec, rtcmin, rtchr, rtcdate, rtcmonth, rtcday, rtcyear, rtccontrol]
RST = 0 ' Reset RTC
Return  'return control to calling module

End

[Byte_Butcher]

Hmmm. I don't see any code to initialize the RTC. Add something like this to your code, so it runs once before you enter the main loop....
You'll have to look in the data sheet to set your preferred trickle charge rates and such if you are going to use the charger.

'initialize the RTC and set the trickle charge rate
Low SCLK
low rst        ' Reset RTC
high rst       ' RTC Ready for transfer        
Shiftout IO, SCLK, LSBFIRST, [$8e, 0]  ' Enable write
low rst        
high rst
Shiftout IO, SCLK, LSBFIRST, [$90, %10101011]  ' Set charger on and to "2 diodes, 8Kohm"              
Low RST         ' Reset RTC

steve