37 PPC-157T User ManualChapter 5 Jumpers and ConnectorsTable 5.19: CN26 (COM1 RI Function Selection Connector)Pin Signal1 COM1_RI2 COM1_RI_Selection3 +V54 COM1_RI_Selection5 +V12Table 5.20: CN28 (LCD Back Light Connector)Pin Signal1 +V122 +V123 GND4 GND5 LCD_BKLTEN6 LCD_VBR7 LCD_DETTable 5.21: CN29 (Power Button Connector)Pin Signal1 PANSWIN2 GNDTable 5.22: CN34A (COM3 RS-232 serial port)Pin Signal Pin Signal1 DCD# 2 RX3 TX 4 DTR#5 GND 6 DSR#7 RTS# 8 CTS#9 RI#Table 5.23: CN34B (VGA)Pin Standard Connect1 59632 47 8