The DSP28335 processor is used to communicate with the M41T94 real-time clock chip (RTC). The RTC uses SPI for communication. The basic configuration method is to write command + write time, then read command + read time, but the read time is basically unchanged. The year, month, date, and time information (8 bytes) sent by my oscilloscope decoding is shown in Figure 1 below. But when I read the data continuously, it reads all ff or 00, as shown in Figure 2 (channel 1 is sclk, channel 2 is mosi, channel 3 is miso, channel 4 is chip enable). I don't know if the problem occurs because the command is not written in or the hardware is the problem. The hardware is shown in Figure 3.
Hope to get your help.
