Both RESET# and WP# pins have an internal pull up resistor and can be left unconnected, if not used.
Are the SPI signals shared between the two flash devices (S70FL01GS and S25FS512S)? Could you please attach the schematic diagram of your application? Where did you probe to collect the attached scope shot? Is it on the pins of S25FS512S flash device?
Thanks and Regards,
Hello, and thank you for the reply.
I attach you the schematic of the board where the S25FS512S are on.
the MOSI and the SCLK are shared except of the level shifters in between.
The bottom signal on the scope is probed on the S25FS512S MISO which is
left open for the probing.
the three middle are also probed on the pins of the S25FS512S
The Top signal on the scope is probed on the S70FL01GS MISO, directly on
DAHLIA_MAIN_BOARD_V1.0-2.pdf 65.5 K
I checked the schematic diagram that you attached. There are 6 S25FS512S flash devices present on your board. Are you facing this issue with all of them? Also, I did not see any S70FL01GS devices connected in the schematic diagram. Could you please clarify, how you probed both the devices at the same time?
Thanks and Regards,
yes, i face the same issue on all devices.
The whole system is comprised of many boards,. i attach you now also the
board of the level shifters and the board of the S70FL01GS that also
contains an MCU. They are connected through the connectors.
I notice that the MISO on the S70FL01GS starts from 1. Do i have to weak
pull up the MISO?
You mentioned earlier that RESET# and WP# are stuck at 0. This should not be the case otherwise this would mean that the part is in continuous reset mode. Please double check!
Please also check your power supply and that you comply with the Power On reset specification from the datasheet, e.g: CS# should ramp up with VCC, VCC should not have power drops...
It looks like the S25FS512S units are not responding at all. Please check that their corresponding CS# signals are being driven properly and one device is selected at a time, because otherwise you get into bus contention.