Board HC12
The HC12 module is an RF RS232 radio link module based on the versatile "sub-GHz" Si4463 radio modem chip. The module is designed to operate in the 433MHz ISM band, and uses the Si4463 packet handler for data transfer.
List from al177/stm8ef:
| Pin# | Function | board pin/signal |
|---|---|---|
| 1 | PD4 | Si4463 p1 - SDN |
| 2 | PD5/UART1_TX | header TXD pad via level shifter |
| 3 | PD6/UART1_RX | header RXD pad via level shifter |
| 4 | nRST | reset test point nearest header RXD pad |
| 11 | PB5 | header SET pad via level shifter |
| 12 | PB4 | Si4463 p9 - GPIO0 |
| 13 | PC3 | Si4463 p10 - GPIO1 |
| 14 | PC4 | Si4463 p11 - nIRQ |
| 15 | PC5/SPI_SCK | Si4463 p12 - SCLK |
| 16 | PC6/SPI_MOSI | Si4463 p14 - SDI |
| 17 | PC7/SPI_MISO | Si4463 p13 - SDO |
| 18 | PD1/SWIM | SWIM test point nearest header TXD pad |
| 19 | PD2 | Si4463 p15 - nSEL |
Command 0x13 GPIO_PIN_CFG: configuration if the GPIO pins 0x60,0x48,0x57,0x56,0x5A,0x4B.
| Pin | Init | Pullup | Mode | Mode Description |
|---|---|---|---|---|
| GPIO0 | 0x60 | 1 | 32 | High while in the transmit state. |
| GPIO1 | 0x48 | 1 | 8 | CTS. Output High when clear to send a new command, output low otherwise. |
| GPIO2 | 0x57 | 1 | 23 | Antenna 2 Switch used for antenna diversity. |
| GPIO3 | 0x56 | 1 | 22 | Antenna 1 Switch used for antenna diversity. |
| NIRQ | 0x5A | 1 | 26 | High when a sync word is detected. Returns to output low after the packet is received. |
| SDO | 0x4B | 1 | 11 | SPI. Serial data out. |
Note: before transmit, the configuration of GPIO2 and GPIO3 is swapped, and swapped back again after transmission. This is not entirely surprising since antenna diversity has nothing to do with the RX/TX switch on the PCB.
The API and the configuration of the Si4463 depends on the chip revision, and the HC12 uses the revision Si4463B1B. Judging from the range of information offered on the Silicon Labs web site the B1B appears to be a "stable" product revision, and the HC12 module is not likely to apply a different revision anytime soon.
Using a logic analyzer, the following Si4463 API calls were recorded HC12 init in default mode (9600 baud, default frequency). The values were verified by repeated read-out.
0,0x02,0x01,0x00,0x01,0xC9,0xC3,0x80
1,0x13,0x60,0x48,0x57,0x56,0x5A,0x4B
2,0x11,0x00,0x01,0x00,0x48
3,0x11,0x00,0x01,0x03,0x40
4,0x11,0x01,0x01,0x00,0x00
5,0x11,0x02,0x04,0x00,0x03,0x07,0x00,0x00
6,0x11,0x10,0x09,0x00,0x06,0x14,0x00,0x50,0x31,0x00,0x00,0x00,0x00
7,0x11,0x11,0x05,0x00,0x21,0x89,0x89,0x00,0x00
8,0x11,0x12,0x01,0x00,0x81
9,0x11,0x12,0x01,0x06,0x02
10,0x11,0x12,0x03,0x08,0x00,0x00,0x00
11,0x11,0x12,0x0C,0x0D,0x00,0x40,0x06,0xAA,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00
12,0x11,0x12,0x08,0x19,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00
13,0x11,0x20,0x0C,0x00,0x03,0x00,0x07,0x26,0x25,0xA0,0x01,0xC9,0xC3,0x80,0x00,0x22
14,0x11,0x20,0x01,0x0C,0x22
15,0x11,0x20,0x08,0x18,0x01,0x00,0x08,0x03,0x80,0x00,0x00,0x30
16,0x11,0x20,0x09,0x22,0x00,0x78,0x04,0x44,0x44,0x04,0x44,0x02,0x00
17,0x11,0x20,0x07,0x2C,0x00,0x23,0x8F,0xFF,0x00,0xDE,0xA0
18,0x11,0x20,0x01,0x35,0xE2
19,0x11,0x20,0x09,0x38,0x22,0x0D,0x0D,0x00,0x1A,0x40,0x00,0x00,0x28
20,0x11,0x20,0x0B,0x42,0xA4,0x03,0xD6,0x03,0x01,0x0A,0x01,0x80,0xFF,0x0C,0x00
21,0x11,0x20,0x01,0x4E,0x40
22,0x11,0x20,0x01,0x51,0x0A
23,0x11,0x21,0x0C,0x00,0x5B,0x47,0x0F,0xC0,0x6D,0x25,0xF4,0xDB,0xD6,0xDF,0xEC,0xF7
24,0x11,0x21,0x0C,0x0C,0xFE,0x01,0x15,0xF0,0xFF,0x03,0x5B,0x47,0x0F,0xC0,0x6D,0x25
25,0x11,0x21,0x0C,0x18,0xF4,0xDB,0xD6,0xDF,0xEC,0xF7,0xFE,0x01,0x15,0xF0,0xFF,0x03
26,0x11,0x22,0x04,0x00,0x08,0x7F,0x00,0x5D
27,0x11,0x23,0x07,0x00,0x01,0x05,0x0B,0x05,0x02,0x00,0x03
28,0x11,0x30,0x0C,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00
29,0x11,0x40,0x08,0x00,0x38,0x0D,0xDD,0xDD,0x36,0x9D,0x20,0xFE
30,0x20,0x00,0x00,0x00
31,0x11,0x20,0x0C,0x00,0x03,0x00,0x07,0x00,0xEA,0x60,0x04,0x2D,0xC6,0xC0,0x00,0x04
32,0x11,0x20,0x01,0x0C,0x19
33,0x11,0x20,0x08,0x18,0x01,0x80,0x08,0x03,0x80,0x00,0x20,0x10
34,0x11,0x20,0x09,0x22,0x00,0xA7,0x03,0x12,0x6F,0x01,0x88,0x02,0xC2
35,0x11,0x20,0x07,0x2C,0x04,0x36,0x80,0x2C,0x07,0xE9,0x80
36,0x11,0x20,0x09,0x38,0x11,0x25,0x25,0x00,0x1A,0x80,0x00,0x00,0x29
37,0x11,0x20,0x0B,0x42,0xA4,0x02,0xD6,0x83,0x01,0x44,0x01,0x80,0xFF,0x0C,0x00
38,0x11,0x21,0x0C,0x00,0xCC,0xA1,0x30,0xA0,0x21,0xD1,0xB9,0xC9,0xEA,0x05,0x12,0x11
39,0x11,0x21,0x0C,0x0C,0x0A,0x04,0x15,0xFC,0x03,0x00,0xCC,0xA1,0x30,0xA0,0x21,0xD1
40,0x11,0x21,0x0C,0x18,0xB9,0xC9,0xEA,0x05,0x12,0x11,0x0A,0x04,0x15,0xFC,0x03,0x00
41,0x11,0x22,0x04,0x00,0x08,0x7F,0x00,0x3D
42,0x11,0x23,0x07,0x00,0x2C,0x0E,0x0B,0x04,0x0C,0x73,0x03
43,0x11,0x22,0x01,0x01,0x7F
44,0x15,0x00
45,0x44,0xFF
46,0x44,0xFF
47,0x44,0xFF,0xFF,0xFF
48,0x33
49,0x44,0xFF
49,0x44,0xFF,0xFF,0xFF,0xFF
50,0x44,0xFF,0xFF,0xFF,0xFF
51,0x32,0x02,0x00,0x00,0x14,0x00,0x01,0x03