STM32F103C8 (BluePill) based temperature node with relay

Features

variable power supply: 5-15V (depends on relay coil)
1-wire bus for DS18B20 temperature sensors
1x thermistor input
1x SPST relay with ARC suppression
controlled over MQTT

MQTT topics

nameOfBoard/dtemp/* = dallas temperature (aterisk is temp address)
nameOfBoard/atemp/* = thermistor temperature (aterisk is analog temp index)
nameOfBoard/status = online status
nameOfBoard/err = dallas error, tells you index of the bad sensor
nameOfBoard/count = number of dallas sensors found
nameOfBoard/relay/0 = state of relay
nameOfBoard/relay/0/set = command for relay, can be either 0 or 1

BOM

Qty	Component	Value	Package
1	Ceramic capacitor	10uF	C0805
1	Electrolytic capacitor	100uF	E2-5
1	Polypropylene capacitor	R463I24705001K	C150-084X183
1	Diode	S1B	DO214AC (SMA)
1	Shottky diode	SS16	DO214AC (SMA)
1	Barrel jack	2.1mm
1	Relay	RM85-2021-35-1005
1	NPN transistor	BC817	SOT23-BEC
1	Resistor	1K	R0805
1	Resistor	4K7	R0805
1	Resistor	10K	R0805
1	Resistor	160R	R2010
1	Ethernet module	ENC28J60
1	LDO regulator	LM1117-3.3	SOT223
1	Processor module	STM32F103C8T6
2	Terminal	Wago 236-740-5,08
1	Terminal	KF350-3.50-2P
3	Terminal	KF350-3.50-3P
1	Case	KRADEX Z76