I'm using MK64, the FB_RW keeps being low after the write operation is finished, and the FB_RW returns high after the read operation, which seems to be 6800 mode, I need 8080 mode
Hi,
From the attached FlexBus timing, it is incorrect, at least, the data bus should be valid until the rising edge of /CS signal.
Pls try different parameter in the FB_CSCRn register, especially, WRAH and WS bits, do not use burst mode, set AA bit in 1.
Pls have a try.
BR
XiangJun Rong
The DM9000 write timing is shown in the figure, how does the MK64 FlexBUS implement it?
As you can see from the graph, the FB_RW stays low after the data is written
Hi,
The Flex_Bus of K64 is in 8086 mode instead of 68K mode.
This is the reading timing:
This is writing timing:
Compare the two timing, you can see that the /FB_OE low and the FB_RW high are observed in reading timing, the /FB_OE high and the FB_RW low are observed in writing timing.
If the timing is 68K mode, the /FB_OE is always low no matter whether it is reading or writing.
Hope it can help you
BR
XiangJun Rong