Datasheet

VS1053b Datasheet
11 VS1053B REGISTERS
11.10 GPIO
GPIO registers, prefix GPIO_
Reg Type Reset Abbrev[bits] Description
0xC017 rw 0 DDR[9:0] Direction
0xC018 r 0 IDATA[11:0] Values read from the pins
0xC019 rw 0 ODATA[8:0] Values set to the pins
GPIO_DIR is used to set the direction of the GPIO pins. 1 means output. GPIO_ODATA
remembers its values even if a GPIO_DIR bit is set to input.
GPIO_IDATA is used to read the pin states. In VS1053 also the SDI and SCI input pins
can be read through GPIO_IDATA: SCLK = GPIO_IDATA[8], XCS = GPIO_IDATA[9], SI =
GPIO_IDATA[10], and XDCS = GPIO_IDATA[11].
In addition to data direction control for GPIO pins 0 to 7, there are two additional control bits in
GPIO_DIR. GPIO_DIR[8] switches SO into software control, so that the value in GPIO_ODATA[8]
is shown on SO whenever xCS is low. When GPIO_DIR[9] is set to ’1’ SCI and SDI are dis-
abled. When using SCLK, xCS, SI and xDCS as general-purpose input, GPIO_DIR[9] prevents
transitions in them from getting random data from SDI and/or SCI.
GPIO registers don’t generate interrupts.
Note that in VS1053b the VSDSP registers can be read and written through the SCI_WRAMADDR
and SCI_WRAM registers. You can thus use the GPIO pins quite conveniently.
Version: 1.22, 2014-12-19 75