AirPrime Module Datasheet

Hardware Design Guidelines
Rev 1 Apr.17 25 41110693
GPIO and UART
The BC127/BC127-HD/BC127-EXT is controlled by GPIOs. This can be
configured. If GPIO control is not used, these GPIOs should be left floating. The
UART by default does not use RTS/CTS flow control. If the users do not expect to
use it, these lines should be left floating.
Digital Pin States on Reset or After Power Up
The following table shows the Digital Pin States on Reset or after power up.
PD = Pull Down, PU = Pull Up
Table 4-2: Digital Pin States on Reset or after Power up
Pin Name/Group I/O Type State after Power Up or
Reset
USB_DP Digital bi-directional N/A
USB_DN Digital bi-directional N/A
UART_RX Digital bi-directional with PU Strong PU
UART_TX Digital bi-directional with PU Weak PU
UART_CTS Digital bi-directional with PD Weak PD
UART_RTS Digital bi-directional with PU Weak PU
SPI_CS# Digital input with PU Strong PU
SPI_CLK Digital input with PD Weak PD
SPI_MISO Digital tri-state output with PD Weak PD
SPI_MOSI Digital input with PD Weak PD
SPI_PCM# Digital bi-directional with PD Strong PD
PCM_IN Digital bi-directional with PD Weak PD
PCM_OUT Digital bi-directional with PD Weak PD
PCM_SYNC Digital bi-directional with PD Weak PD
PCM_CLK Digital bi-directional with PD Weak PD
RST# Digital input with PU Strong PU
PIO[7:0] Digital bi-directional with PD Weak PD