Other Parts Discussed in Thread: AM3358
Hi,
I have designed a board with Beaglebone Black as a close reference.
CPU: AM3352BZCZA80
RAM: ISSI IS43TR16256AL-125KBL (DDR3L, datasheet)
PMIC: TPS65217D
JTAG: XDS200
Code Composer Studio v8.2
The issue is that I can not talk to the RAM and thus cannot run DDR3_slave_ratio_search_auto.out to find optimal parameters.
I have tested three boards so far, and on two of them I can't talk to RAM at all as it seems, I can not get a value to stick in the RAM when updating an address in the memory browser.
On one board there is random toggling of random addresses between 0x00000000 and 0x00FF00FF.
Here is a GIF showing the memory browser at 0x80000000 and forward with the toggling issue:
I've tried with both 303 MHz and 400 MHz speeds to the RAM.
Attached is my updated GEL with values for 400 MHz clock. Also attached is an Excel-file with the lengths in mil of all DDR3 signals.
I have read the wiki a lot and even tried using the GEL from BBB (with my timing values) but with no luck. Running the GEL on an actual BBB works, of course.
VDDS_DDR is steady at 1.354V and DDR_VREF is at 0.678V.
I would appreciate if I could get some help or ideas. It would be nice to get a second opition on my timing values, so I now they are ok.
Thanks in advance!