1. Maximum operating frequency of 72MHz, achieving 1.25DMips/MHz during 0-wait-cycle memory access
2. Single-cycle multiplication and hardware division
3. 64K flash program memory
4. 20K-byte SRAM
5. 2.0-3.6V power supply and I/O pins
Programmable Voltage Monitor (PVD) 6. Power-On/Power-Down Reset (POR/PDR)
7. 4-16MHz crystal oscillator
8. Embedded factory-calibrated 8MHz RC oscillator
9. Embedded calibrated 40KHz RC oscillator
10. PLL generating CPU clock
11. Calibrated 32KHz RTC oscillator
12. Sleep, halt, and standby modes
13. VBAT supplies backup registers for RTC
14. Two 12-bit ADCs with 1μs conversion time (up to 16 input channels)
15. DMA
16. 37 high-speed I/O ports; all I/O pins can be mapped to 16 external interrupts; nearly all ports tolerate 5V signals
17. 3 general-purpose timers, one advanced timer
18. 2 (SPI1, SPI2)
19. 2 (I2C1, I2C2)
20. 3 (USART1, USART2, USART3)
21. 1 (USB 2.0 Full-Speed)
22. 1 (USB 2.0 Type-B Host)
Shipping matters：
China Post Small Parcel： 15-20 days
EMS：10-15 days
FedEx：5-7 days
DHL Express：5-7 days
UPS：4-7 day
Receive order preparation time:
Ships 1-3 days after receipt of order
Tax issues:
1. As each country charges different taxes on parcels, you need to know whether the country of your own address needs to charge taxes before placing an order.
2. If you need to reduce the invoice amount, you can contact customer service or e-mail contact.
3.The package arrives safely in the buyer’s country and the merchant is not responsible if the package is (returned) because the buyer has not paid the tax.
Other issues:
If you need to find other electronic products or have any questions you can contact customer service or email. (We will get back to you as soon as possible)
