??? 01/31/07 12:50 Read: times |
#131784 - What is the current problem? Responding to: ???'s previous message |
Does that look better? Yes. The new trace is fine. - SCK is '0' in idle phase - MOSI is stable at the rising edge of SCK, and altered at the falling edge of SCK. - MOSI correctly outputs 04h 01h 0Dh 9Ch 36h 01h sequence. Also from the previous trace, - CS (SS) has enough lead time from the rising edge of the first SCK - CS also has enough hold time after the rising edge of the last SCK - CS is clocked every 2 bytes. Is CS (SS) is held low while single byte transfer? I can't see it because CS and SCK is overlapped in its height on the trace. However - still no luck. What is your current problem? I cannot find any problem from your scope trace. Check the pin connection. AT89C51 MAX6957 SCK - SCLK MOSI - DIN MISO - DOUT extra port - /CS Tsuneo |