Differences

This shows you the differences between two versions of the page.

--- stm32f1xx [2016/06/18 20:34] – [blue pill] kingkevin
+++ stm32f1xx [2017/07/24 10:54] – [maple mini] typo kingkevin
@@ Line 72: / Line 72: @@
   * proper USB disconnect circuit (useful for using the DFU bootloader it comes with)
   * small
-  * good analogue design
+  * good analog design
   * more flash (128 vs 64 kB)
   * small, fits breadboard (600 mil wide)
@@ Line 79: / Line 79: @@
   * no additional connections (SWD, power, GND)
   * the pin silkscreen are not the chip pins (you always need the schematic at hand)
-  * the clones don't provide a second voltage regulator for the analague part
+  * the clones don't provide a second voltage regulator for the analogue part
 ===== blue pill =====
@@ Line 97: / Line 97: @@
     * 6: -40 to 85 °C
   * peripherals:
-    * 2x20 GPIO pins on the side (most MCU pins are accessible)
+    * two 1x20 GPIO pins headers on the side (most MCU pins are accessible)
     * USB micro-B
     * SWD on the top
     * boot select
     * power LED
-    * user LED, on P13
+    * user LED, on PC13 (warning: switching this LED heavily affects the RTC)
     * reset button (NRST)
     * 32.768 kHz real time clock (RTC)
@@ Line 118: / Line 118: @@
 Mine for example has a 10 kΩ pull-up (to 3.3 V) resistor on USB D+/PA12 instead if a 4.7kΩ (to 5 V), although USB devices use a 1.5 kΩ resistor to pull up (to 3.3 V) usually.
+===== core board =====
+{{ :stm32f1xx:core-board_back.jpg?0x400|core board}}{{ :stm32f1xx:core-board_front.jpg?0x400|core board}}
+You can often find this versatile board for $6 by searching for "51 core board".
+It has:
+  * [[http://www.st.com/web/catalog/mmc/FM141/SC1169/SS1031/LN1565/PF164476|STM32F103C8T6]] MCU ([[http://www.st.com/st-web-ui/static/active/en/resource/technical/document/datasheet/CD00161566.pdf|DS5319 datasheet]], {{:stm32f1xx:CD00161566-STM32F103x8_datasheet.pdf|archive}}):
+    * STM32: 32-bit ARM
+    * F: general purpose
+    * 103: medium density (performance line)
+    * C: 48 pins
+    * 8: 64 kB flash
+    * T: LQFP
+    * 6: -40 to 85 °C
+  * peripherals:
+    * two 2x10 GPIO pin headers on the side (most MCU pins are accessible)
+    * USB micro-B
+    * 2x3 SWD+UART port
+    * boot select
+    * power LED
+    * user LED, on PA1
+    * reset button (NRST)
+    * user button (PA8)
+    * 32.768 kHz real time clock (RTC)
+{{ :stm32f1xx:core-board_schematic.jpg?0x400|}}
+It offers quite a lot of peripheral options:
+  * 2x4 header for the ESP-01 WiFi module (base on the ESP8266)
+  * 2x4 header for the nRF24L01 transceiver module
+  * 1x4 header for a Bluetooth module (using as UART port)
+  * 1x8 header for an OLED/TFT screen
+  * 2x5 header for a VS1053/W5500 Ethernet module
+  * space and pads for a CR1220 coin cell (with knife pins) connected to VBAT (for the the RTC circuit of the micro-controller), but don't forget to also add the two diodes (D3 and D4)
+  * footprint for a flash chip (W25xxx, SOP-8) connected to an SPI port (SPI1)
+  * footprint for a EEPROM chip (24Cxx, SOP-8) connected to an I2C port (I2C1), but don't forget to add the pull-up resistors (R12 and R13)
+  * footprint for a [[https://www.aliexpress.com/item/20PCS-Push-Push-Type-TransFlash-TF-Micro-SD-Card-Socket-Adapter-Automatic/32596334297.html|micro-SD card slot]] connected to an SPI port (SPI1), but don't forget to add the pull-up resistors (R14, R15, and R16)
+advantages:
+  * user LED and button
+  * large AMS1117 voltage regulator
+  * fuse on USB 5V
+  * separate 5V connection
+  * SWD+UART header (ideal for the black magic probe)
+  * RTC oscillator included
+  * compact (42x53 mm)
+  * M3 mounting holes
+drawbacks:
+  * very few power pins
+**warning**: on the board silkscreen SWDIO and SWCLK are swapped
 ====== flashing ======