AAEON TKS-G20-LN05 Rev.B - Manual (Page 22)

E m b e d d e d C o n t r o l l e r T K S - G 2 0 - L N 0 5 R e v . B
Chapter 2 Quick Installation Guide 2 - 8
3 RXD+ 4 N/C
5 TXD+ 6 N/C
7 RXD- 8 N/C / +5 Volt. / (+12 Volt.)
9 Ground 10 N/C
RS-485 Mode
Pin Signal Pin Signal
1 TXD- 2 N/C
3 N/C 4 N/C
5 TXD+ 6 N/C
7 N/C 8 N/C / +5 Volt. / (+12 Volt.)
9 Ground 10 N/C
Note:
Issue: COM port limitation for the speed test during the communication.
Root Cause:
In serial communication, data bits received at the serial port are bundled
into a byte and transmitted into the serial port hardware buffer. From the
buffer, the byte is sent into the CPU. If a new byte arrives before the byte
in the buffer is moved into the CPU, a Hardware Overrun Error occurs.
Solution:
1. Try hardware handshaking.
2. See if the UART is an older un-buffered version or a new buffered
UART (such as a 16550A or 16750). You should use a buffered UART
for the reasons discussed above.
3. Change the Receive (Rx Trigger) buffer to 8, 4, or 1 (1 is a last resort).
4. For the product, the speed setting of Series Port (COM) is under
9600bps.