8.1 RTS/CTS Handshake
Transmission of RTS, combined with reception of CTS, allows for hardware handshaking (data flow control) between the UART and the external device. RTS is transmitted on AUXOUT by connecting pins 4 and 5 of the jumper block. CTS is received on AUXIN by connecting pins 1 and 2 of the jumper block. If RTS/CTS handshaking is not desired, the RTS output can be looped back to the CTS input by connecting pins 1 and 4 of the jumper block. Figure 19 shows how to select the RTS/CTS mode.
Jumpers J5, J7
XCLK 6 | 3 | RCLK | XCLK 6 | 3 | RCLK |
AUXOUT 5 | 2 | AUXIN | AUXOUT 5 | 2 | AUXIN |
RTS 4 | 1 | CTS | RTS 4 | 1 | CTS |
Transmit RTS on AUXOUT | Loopback RTS to CTS | ||||
Receive CTS on AUXIN |
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Figure 19 --- RTS/CTS selection
8.2 RCLK
This is the clock signal used by the receiver portion of the UART. It is generally provided by connecting it to the UART's own transmit clock output (XCLK). This is done by connecting pins 3 and 6 of the jumper block. If desired, RCLK can be received from an external source over the AUXIN line by connecting pins 2 and 3 of the jumper block. Figure 20 shows how to select the RCLK mode.
Jumpers J5, J7
XCLK 6 | 3 | RCLK | XCLK 6 | 3 | RCLK |
AUXOUT 5 | 2 | AUXIN | AUXOUT 5 | 2 | AUXIN |
RTS 4 | 1 | CTS | RTS 4 | 1 | CTS |
Loopback XCLK to RCLK | Receive RCLK on AUXIN | ||||
Figure 20 --- RCLK selection
Quatech | 30 |