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Hey,
I want to be able to use 3.3V logic on my I2C lines of CY8Ckit-059, however I still want to be able to have my KitProg plugged in and get data from it and continue to be able to program my PSOC. Is this possible? How do I do it?
Solved! Go to Solution.
- Labels:
-
ispn:39618:1:0
-
l1:314:1:0
-
PSoC5LP
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Hi,
Note: Dear /odissey1-san, please correct me if I'm wrong
SDA pin and SCL pin are configured as open-drain, so it will not be driven to High (5V).
So "IMHO", as far as you connect only SDA, SCL and GND to CY8CKIT-059 and
you pull-up SDA and SCL lines with 3.3V, the 3.3V logic group will be fine and
PSoC can access I2C without destroying the 3.3V logic group.
moto
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amcl,
Port 12 on KIT-059 is a Special pins (SIO), which can serve as logic level translator for I2C operating at 3.3V , while the rest of PSoC is at 5V. Please read AppNote on SIO use
https://www.cypress.com/documentation/application-notes/an60580-sio-tips-and-tricks-psoc-3-psoc-5lp
Note that I2C communication requires 10k pull-up resistors on both SCL and SDA lines for proper operation.
/odissey1
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Hi,
Note: Dear /odissey1-san, please correct me if I'm wrong
SDA pin and SCL pin are configured as open-drain, so it will not be driven to High (5V).
So "IMHO", as far as you connect only SDA, SCL and GND to CY8CKIT-059 and
you pull-up SDA and SCL lines with 3.3V, the 3.3V logic group will be fine and
PSoC can access I2C without destroying the 3.3V logic group.
moto
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Motoo,
Yes, this should work as long as pins are set to open drain drives low.
/odissey1
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Dear /odissey1-san,
> Yes, this should work as long as pins are set to open drain drives low.
Thank you 😉
Best Regards,
19-Sep-2019
Motoo Tanaka