I attempt to initialize the sja1000 in Pelican Mode and BasicCan Mode. After I enable the interrupt register, the interrupt output can not be drive to low. There are some phenomenons during the debug. I can not explain them. So please help me.
1. According to my requirement the Pelican Mode should be used. I initialize the sja1000 as the sequence described on AN97076. After I config the clock divider register(addr=0x1F) with 0xC0, the Pelican Mode can not be entered. I read all the registers about the initialization. The out is the content in the address of BasicCAN Mode.
2. When I change the bit0~bit2 of clock register and read this register the bit0~bit2 are always be zeros. The frequency of CLKOUT PIN doesn't change. The clock register may not work.
3. Then I attempt to initialize the sja1000 in BasicCan Mode. I read all the register after I write the. The read and write is okay except the clock divider register. I check the control register(addr=0x00, data= 0x3e). All the interrupts are be enabled but there are no interrupt.
I don't know how to deal with is. Please help me.