TS-7180 COM Ports
The TS-7180 provides three standard RS-232 ports, and one RS-485 port. A fourth RS-232 port is a non-standard option. All of these ports are presented on the P5 connector. The RS-485 port has auto-transmit-enable and an on-board terminator that may be enabled by installing the "485" jumper (adjacent to the RTC battery).
RS-232 ports 1 through 3
| UART | Linux /dev | Connection on Terminal Block P5-A | To "steal [1]" | TX pin | RX pin |
|---|---|---|---|---|---|
| UART2 | ttymxc1 | TX2/RX2 | 5 | 6 | |
| UART5 | ttymxc4 | TX1/RX1 | 2 | 3 | |
| UART7 | ttymxc6 | TX3/RX3 (unless "stolen") | 4 | 7 | 8 |
- ↑ Writing this value to FPGA address 307 or 308 takes over this UART device for the cell modem or HD12, respectively. While "stolen", this physical RS-232 connection no longer possesses a UART device.
| Note: | The RS-232 transceiver chip on the board must be enabled before those ports can be used. This is done by running the command tshwctl -a 21 -w 3.
|
RS-485
| UART | 485+ | 485- |
|---|---|---|
| ttymxc3 | P5-13 | P5-14 |
RS-485 on the P5 terminal block is accessible via /dev/ttymxc3, unless that device is "stolen" for RS-232 on the XBee/Nimbelink/MultiTech sockets or the HD12 header.
RS-232 port 4 (optional)
Custom boards may provide a fourth RS-232 port on P5, taking over the pins that by default are assigned to the second CAN controller. In this case, the pinout of the additional RS-232 port is:
| UART | TX | RX |
|---|---|---|
| ttymxc7 | P5-10 | P5-11 |
The daughter-card interface (HD12 header) contains TTL-level TX/RX pins that may be used to connect to a CPU UART, with the caveat that to do so, one of the assigned UARTs must be reassigned to the header. The reassignment is done by writing to the register at address 308 in the FPGA. The table in the FPGA Registers section shows which UARTs may be reassigned. By default, the HD12 TX/RX pins are not connected to any UART.