CSR BlueCore CSR8640 BGA, User Manual

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8 Interfaces
8.1 Programmable I/O Ports, PIO
CSR8640 BGA provides 22 lines of programmable bidirectional I/O, PIO[21:0]. Some of the PIOs on the
CSR8640 BGA have alternative functions, see Table 8.1.
PIO
Function
Debug SPI
(See Section 7.3) SPI Flash
(See Section 6.5) UART
(See Section 7.2) PCM
(See Section 9.3) EEPROM
(See Section 7.4)
PIO[2] SPI_MOSI - - PCM1_IN -
PIO[3] SPI_MISO - - PCM1_OUT -
PIO[4] SPI_CS# - - PCM1_SYNC -
PIO[5] SPI_CLK - - PCM1_CLK -
PIO[10] - QSPI_FLASH_CLK - - I2C_SCL
PIO[11] - QSPI_IO[0] - - I2C_SDA
PIO[12] - QSPI_FLASH_CS# - - I2C_WP
PIO[13] - QSPI_IO[1] - - -
PIO[14] - - UART_RX - -
PIO[15] - - UART_TX - -
PIO[16] - - UART_RTS - -
PIO[17] - - UART_CTS - -
Table 8.1: Alternative PIO Functions
Note:
See the relevant software release note for the implementation of these PIO lines, as they are firmware build-
specific.
8.2 Analogue I/O Ports, AIO
CSR8640 BGA has 1 general-purpose analogue interface pin, AIO[0]. Typically, this connects to a thermistor for
battery pack temperature measurements during charge control. See Section 12 for typical connections.
8.3 LED Drivers
CSR8640 BGA includes a 3-pad synchronised PWM LED driver for driving RGB LEDs for producing a wide range
of colours. All LEDs are controlled by firmware.
The terminals are open-drain outputs, so the LED must be connected from a positive supply rail to the pad in series
with a current-limiting resistor.
Advance Information
This material is subject to CSR's non-disclosure agreement
© Cambridge Silicon Radio Limited 2011
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