PymateIO-Expansion-Connector
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Abstract
The Pymate Expansion connector is used to connect Pymate expansion board to Pymate Core.
Most of the expansion (like 16ADI16DO) relies on the CAN bus.
Some other expansion (like Ethernet) relies on SPI bus. Some extra pin may also be reconfigured to support the target expansion.
Do not sacrifice the I2C bus to convert their lines into GPIOs!
Indeed, I2C can be used to add a GPIO expander (mcp23017, mcp23008, pcf9536, tca9554a) controlling additional GPIOs.
Such GPIO expander can be used for additional input/output, new nss lines for the SPI bus, digital switch activation for UART and much more!
Expansion Connector
| Pin | Name | Type | Description |
|---|---|---|---|
| 1 | /SRST | Placed LOW when reset is activated. | |
| 2 | GND | Power | Common Ground |
| 3 | I2C4_SCL | I2C | I2C Bus clock signal. |
| 4 | I2C4_SDA | I2C | I2C Bus data signal. |
| 5 | I2C4_SMB | GPIO | Can be used as GPIO, Interrupt Pin, OneWire, second SPI bss.
Usage depends on connected expansion. |
| 6 | SPI1_MOSI | SPI | SPI Master Out data line |
| 7 | SPI1_MISO | SPI | SPI Master In data line |
| 8 | SPI1_SCK | SPI | SPI Clock line |
| 9 | SPI1_NSS | GPIO | GPIO also used as SPI Slave Select line |
| 10 | TX | UART | |
| 11 | RX | UART | |
| 12 | CANL | CAN | Same line as CANL connector.
CAN is the main interface bus for Pymate expansion. |
| 13 | CANH | CAN | Same line as CANH connector. |
| 14 | GND | Power | Common Ground |
| 15 | 5V | Power | 5V 1A power source |
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