I am using uart4 for bluetooth on imx6q board on android.
The module i am using is AP6210.But the bluetooth function is unnormal.
The bluetooth module have 4 signals.They are UART_TXD,UART_RXD,UART_CTS_N,UART_RTS_N.So,the imx6 i using UART4_TX,UART4_RX,UART4_RTS,UART4_CTS
my connection is as follows:
in board-mx6q_sabresd.h,i have some define as follows:
in board-mx6q_sabresd.c,i have:imx6q_add_imx_uart(3, NULL);
The bluetooth work unnormal and the supplier of bluetooth told me that the signal of UART_CTS_N in AP6210 should be low voltage. when the module is turning on.Because it was controlled by UART4_RTS in imx6.
I measured the UART_CTS_N signal in AP6210 is high voltage (3.3V) all the time.
So,i would like to say that the UART4_CTS should be special pin or general i/o using?
Can you anyone help me!