MAX-7 / NEO-7 - Hardware Integration Manual
UBX-13003704 - R09 Production Information Hardware description
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behavior. After every byte is read from register 0xFF the internal address counter is incremented by one,
saturating at 0xFF. Therefore, subsequent reads can be performed continuously.
2.6.4 SPI (NEO-7)
With NEO-7 modules, an SPI interface is available for communication to a host CPU.
SPI is not available in the default configuration, because its pins are shared with the UART and DDC
interfaces. The SPI interface can be enabled by connecting D_SEL to ground (NEO-7) (see section 2.7.3).
For speed and clock frequency see the Data Sheet.
Figure 4 shows how to connect a u-blox GNSS receiver to a host/master. The signal on the pins must meet the
conditions specified in the Data Sheet.
Figure 4: Connecting to SPI Master
VCC_IO must have the same voltage level as the host.
2.7 I/O pins
2.7.1 RESET_N: Reset input
Driving RESET_N low activates a hardware reset of the system. Use this pin only to reset the module. Do not use
RESET_N to turn the module on and off, since the reset state increases power consumption. With u-blox 7
RESET_N is an input only.
2.7.2 EXTINT: External interrupt
EXTINT is an external interrupt pin with fixed input voltage thresholds with respect to VCC or VCC_IO (see the
data sheet for more information). It can be used for wake-up functions in Power Save Mode on all u-blox 7
modules and for aiding. Leave open if unused.
2.7.3 D_SEL: Interface select (NEO-7)
The D_SEL pin, available on all NEO-7 modules, selects the available interfaces. SPI cannot be used
simultaneously with UART/DDC.
If open, UART and DDC are available. If pulled low, the SPI Interface is available.
Table 3: D_SEL pin on NEO-7