stm32samples/F3:F303/InterfaceBoard

Multiport board

Seven isolated interfaces:

• 1 CAN
• 3 RS-485
• 2 or 1 RS-232
• 1 SSI or 1 RS-422 (in this case only one RS-232)

Inner USB interfaces (IFx):

1. RS-485 (1)
2. RS-485 (2)
3. RS-485 (3)
4. RS-232 (1)
5. RS-232 (2) or RS-422 (by jumpers)
6. CAN
7. SSI (over SPI, by jumpers) or configuration interface (if "Config mode" jumper opened)

Pinout

Sorted by pin number

Pin #	Pin name	function	settings	comment
1	(VBAT)
2	PC13	NC
3	PC14	NC
4	PC15	NC
5	(OSC IN)
6	(OSC OUT)
7	(NRST)
8	PC0	NC
9	PC1	NC
10	PC2	NC
11	PC3	NC
12	(VREF-)
13	(VREF+)
14	PA0	NC
15	PA1	USART2 DE	AF7 or PP	RS-485 (3) DE
16	PA2	USART2 TX	AF7	RS-485 (3) Tx
17	PA3	USART2 RX	AF7	RS-485 (3) Rx
18	PF4	NC
19	(VDD)
20	PA4	NC
21	PA5	SPI1 SCK	AF5	SSI CLK
22	PA6	SPI1 MISO	AF5	SSI DAT
23	PA7	NC
24	PC4	USART1 TX	AF7	RS-485 (2) Tx
25	PC5	USART1 RX	AF7	RS-485 (2) Rx
26	PB0	(USART1 DE)	PP OUT	RS-485 (2) DE
27	PB1	NC
28	PB2	NC
29	PB10	USART3 TX	AF7	RS-485 (1) Tx
30	PB11	USART3 RX	AF7	RS-485 (1) Rx
31	(VSS)
32	(VDD)
33	PB12	NC
34	PB13	NC
35	PB14	USART3 DE	AF7 or PP	RS-485 (1) DE
36	PB15	NC
37	PC6	NC
38	PC7	NC
39	PC8	NC
40	PC9	NC
41	PA8	NC
42	PA9	(CONF EN)	PU IN	Config jumper
43	PA10	(USB PU)	PP OUT	USB pullup
44	PA11	USB DM	AF14
45	PA12	USB DP	AF14
46	PA13	SWDIO	AF0
47	(VSS)
48	(VDD)
49	PA14	SWCLK	AF0
50	PA15	NC
51	PC10	UART4 TX	AF5	RS-232 (1) Tx
52	PC11	UART4 RX	AF5	RS-232 (1) Rx
53	PC12	UART5 TX	AF5	RS-232(2) / 485 Tx
54	PD2	UART5 RX	AF5	RS-232(2) / 485 Rx
55	PB3	NC
56	PB4	NC
57	PB5	NC
58	PB6	NC
59	PB7	NC
60	(BOOT0)
61	PB8	CAN RX	AF9
62	PB9	CAN TX	AF9
63	(VSS)
64	(VDD)

Some comments.

Interfaces:

• IF1: RS-485 over USART3.
• IF2: RS-485 over USART1.
• IF3: RS-485 over USART2.
• IF4: RS-232 over UART4.
• IF5: RS-232 or RS-422 (by jumpers "IF5" and "SSI") over UART5.
• IF6: CAN bus.
• IF7: SSI (inaccessible when RS-422 selected) or interface for device configuration (if jumper "Config mode" is opened when device started").

DMA1 channels:

• Ch2: USART3_Tx
• Ch3: USART3_Rx
• Ch4: USART1_Tx
• Ch5: USART1_Rx
• Ch6: USART2_Rx
• Ch7: USART2_Tx

DMA2 channels:

• Ch3: UART4_Rx
• Ch5: UART4_Tx

UART5 have no DMA channels, so used in interrupts.

You can try to use hardware DE management on two of RS-485, but I decide that as I can't use hardware DE for all three, it would be simpler to use software DE for all.

Sorted by ports

Pin #	Pin name	function	settings	comment
14	PA0	NC
15	PA1	USART2 DE	AF7 or PP	RS-485 (3) DE
16	PA2	USART2 TX	AF7	RS-485 (3) Tx
17	PA3	USART2 RX	AF7	RS-485 (3) Rx
20	PA4	NC
21	PA5	SPI1 SCK	AF5	SSI CLK
22	PA6	SPI1 MISO	AF5	SSI DAT
23	PA7	NC
41	PA8	NC
42	PA9	(CONF EN)	PU IN	Config jumper
43	PA10	(USB PU)	PP OUT	USB pullup
44	PA11	USB DM	AF14
45	PA12	USB DP	AF14
46	PA13	SWDIO	AF0
49	PA14	SWCLK	AF0
50	PA15	NC
26	PB0	(USART1 DE)	PP OUT	RS-485 (2) DE
27	PB1	NC
28	PB2	NC
55	PB3	NC
56	PB4	NC
57	PB5	NC
58	PB6	NC
59	PB7	NC
61	PB8	CAN RX	AF9
62	PB9	CAN TX	AF9
29	PB10	USART3 TX	AF7	RS-485 (1) Tx
30	PB11	USART3 RX	AF7	RS-485 (1) Rx
33	PB12	NC
34	PB13	NC
35	PB14	USART3 DE	AF7 or PP	RS-485 (1) DE
36	PB15	NC
8	PC0	NC
9	PC1	NC
10	PC2	NC
11	PC3	NC
24	PC4	USART1 TX	AF7	RS-485 (2) Tx
25	PC5	USART1 RX	AF7	RS-485 (2) Rx
37	PC6	NC
38	PC7	NC
39	PC8	NC
40	PC9	NC
51	PC10	UART4 TX	AF5	RS-232 (1) Tx
52	PC11	UART4 RX	AF5	RS-232 (1) Rx
53	PC12	UART5 TX	AF5	RS-232(2) / 485 Tx
2	PC13	NC
3	PC14	NC
4	PC15	NC
54	PD2	UART5 RX	AF5	RS-232(2) / 485 Rx
18	PF4	NC