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???
06/09/05 16:16
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#94566 - C8051F022, Need SPI help with 8051
Responding to: ???'s previous message
Hello ,

I am currently working with Cygnal's C8051F022....I am using the Port 0 for serial communication

My F022 acts as the SPI master.

My SPI is intialized as follows:


mov p0mdout,#015h ( port configuration)
( this is to enable p0.0(TX),P0.2(SCK) and p0.4(MOSI) as push-pull outputs.)



mov spi0cn,#003h ;SPI Control Register
mov spi0cfg,#007h ;SPI Configuration
Register
mov spi0ckr,#063h ;SPI Clock Rate
Register

(this is to configure SPI0 for 8-bit, 172.8 khz SCK,Master mode, data sampled on 1st SCK rising edge)


My sysmtem clk is intialized as follows:(22.1184 Mhz)

mov oscxcn,#067h ;External Oscillator Control
Register
clr a ; osc
djnz acc,$ ; wait for
djnz acc,$ ; at least 1ms

ox_wait:
mov a,oscxcn
jnb acc.7,ox_wait ;poll XTLVLD

mov oscicn,#008h ;Internal Oscillator Control
Register

As far as I know, these are initialized correctly

So there should be an SCK output at P0.2...but there isnt

I dont understand where i am goin wrong..

I am transferring an 8 bit data from the F022 to another slave device..


I have the register R7 whose value changes from time to time.
Every time its value changes, I need F022 to transfer one 8 bit direct value to the slave followed by the 8 bit value of R7.

How can I do this in ASM?

I have tried doing this as follows:
mov spi0cn,#003h
mov spi0cfg,#007h
clr fpga_cs_1
mov spi0dat,#11h
wait_here1:
jnb spi0cn.7,wait_here1
clr spi0cn.7
setb fpga_cs_1
clr fpga_cs_1
mov spi0dat,R7
wait_here2:
jnb spi0cn.7,wait_here2
clr spi0cn.7
setb fpga_cs_1
ret

I am not sure if this is doing it right..

Any ideas or suggestions about this?

Any help is greatly appreciated.

Thank you,

Mahathi


List of 19 messages in thread
TopicAuthorDate
SPI Help            01/01/70 00:00      
   No ?            01/01/70 00:00      
   Do you Strobe your Data?            01/01/70 00:00      
   HW solution            01/01/70 00:00      
      Connection ...            01/01/70 00:00      
         No Strobing            01/01/70 00:00      
            No Strobing -> no way !!!            01/01/70 00:00      
   continuous            01/01/70 00:00      
   use the chips capabilities            01/01/70 00:00      
      I am using hardware            01/01/70 00:00      
         seek and ye shall find            01/01/70 00:00      
      f120 & SPI            01/01/70 00:00      
         Why so narrowminded            01/01/70 00:00      
      real time clock            01/01/70 00:00      
   Re: Why so narrow minded?            01/01/70 00:00      
      93x            01/01/70 00:00      
         C8051F022, Need SPI help with 8051            01/01/70 00:00      
            Re:Mahathi's c8051f022            01/01/70 00:00      
               My master is sending data repeatedly            01/01/70 00:00      

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