Hi,
I am designing a board with STM32L152VD LQFP100. From the datasheet pin definition table When I look for USART3 pins I find pin pairs 55,56 and 78,79 both for USART3. I am sure about pin 55 and 56 since only LQFP100 has it but not sure if pin 78 and 79 are connected to USART3 too.
That depends on the package you are going to use. A 100 pin package may not have all pins available. Perhaps the 144 pin package would have all the pins accessible.
I took a look that 75 and 76 are UART CTS, RTS signals. Also noticed on the 100 part I think I remember that 76 is tied to VDD_2.
As I looked at this document "STM32L151xD STM32L152xD" datasheet (DM00034689.pdf)
on Page 45 there is a table :
Table 8. STM32L151xD and STM32L152xD pin definitions (continued)
You can see that these pins are available on both 100 and 144 pin packages. But not at the same pin numbers:
USART3_CTS/
144 pin package on 74 100 pin package on 52
USART3_RTS/ 144 pin package on 75 100 pin package on 53
Need to look in the right column that corresponds to the packages.
You can also see in the table that some functions available on the die of the chip are not hooked up on the smaller packages. I think the 144 pin chip has all functions hooked up. but the 100 pin chip can not have all functions available. The table shows that.
Functionality can be multiplexed in/out by a number of pin options.
This allows you to escape the specific peripherals you want to use, out of the pin count device you are working with.
The parts generally share a common die (IC), they are just placed in different packages, and a subset of the pins bonded-out.
Review your part's "Data Sheet" to see the peripheral options on each pin, configured via the GPIOx_AFR register.
Thanks for your help. I reviewed once again but I am confused with SPI2_SCK whether on LQFP100 it is pin 52 or 82? I think it is more likely to be 52 since MISO and MOSI are pin 53 and 54. But I see in pin 82 named as SPI2_SCK!
I would try this program
http://www.st.com/stm32cube
And target your device.
It may help you. I imagine though that you can choose either pins since they are in two different places if you know how to configure the part properly.
Dear Gary
Thanks for good suggestion. I tried Cubemx and enjoyed having all the pinout and peripherals. But I don't know why the code generated by this software is different from the libraries I have downloaded from ST and use in my code previously. so I have problem with using the generated code or basically I should begin using the new library having appendix AHL files! Did you have experienced this problem?
Hi Hamed,
I just learning about this. So don't have a lot of knowledge on this topic.
Gary