[bascom] Need Help for DataFlash


From Vanda Dj <vandie@mbox.com.au>
Date Tue, 15 Jan 2002 02:13:17 +1100
Disposition-notification-to vandie@mbox.com.au

Hello,

I'm using Bascom-AVR 1.11.6.2, registered version. I'm trying to get 
AT90S8515 uC to talk to DataFlash chip AT45DB041B, but I can't 
get it working. I use 3.6V Vcc connect to the chip according to the 
Dataflash datasheet. Below is how I connect the chip to the uC:

                     ____________
  PB5 -----------|SI                  SO|------------- PB6
  PB7 -----------|SCk           GND|------------- 0V
  +5V -----------|~RST         VCC|------------- +3.6V
  PB4 -----------|~CS          ~WP|------------- +5V
                     ____________

I also use 10K pull up resister for the Chip_Select pin. And here is 
part of my code I used:

$regfile = "8515DEF.DAT" 
$crystal = 4000000 
Const Cflash_status = &HD7                                  ' read flash 
status 

Dim Flashcmd(4) As Byte 
Spiport Alias Portb 
Const Chip_sel = 4 

Config Spi = Hard , Data Order = Msb , Master = Yes , Clockrate = 
4 
Spiinit 

Declare Sub Df_status 

End 

Sub Df_status: 
Dim Datain As Byte 
  Flashcmd = Cflash_status 

  CBI Spiport,Chip_Sel                                     ' enable DataFlash 
  Spiout Flashcmd , 1                                      ' send command 
  Spiin Datain , 1                                         ' read in data 
  SBI SPIPort,Chip_Sel                                     ' disable 
DataFlash 

  Home Upper 
  Lcd Datain 
End Sub Df_status 

This is what I thought I could check if I can talk to the DataFlash, by 
asking for its status. But it always return 255 for the status instead 
of 10011000 or the like as in the datasheet. Was I doing it right? or 
is there any other ways to check if my DataFlash is still working, that 
I haven't wrecked it.
Any help will be really appreciated.
Thank you in advance,

Regards,
Vanda.
p.s. Sorry about the ad about this message. It comes with the free 
email I'm using.

---------------------------------------------------------------------
NEW EXCITING MESSAGE NOTIFICATIONS FROM mBox
Sign up for mBox Basic or Premium and receive it free!
http://www.mbox.com.au/mBeeper