3.4.6 External Memory
The ZGM230S Dev Kit includes an 8 Mbit Macronix SPI Flash that is connected directly to the ZGM230S. The MX25R series are ultra-
low power serial flash devices, so there is no need for a separate enable switch to keep current consumption down. However, it is im-
portant that the flash is always put in deep power down mode when not used. This is done by issuing a command over the SPI inter-
face. In deep power down, the MX25R typically adds approximately 100 nA to the current consumption. The figure below shows how
the serial flash is connected to the ZGM230S.
ZGM230S
Serial Flash
8 Mbit
MX25R
SPI_COPI
SPI_CIPO
FLASH_SPI_CS
VMCU
SPI_SCLK
PC03
PC01
PC02
PC00
Figure 3.10. Serial Flash
3.4.7 Push Buttons, Single-color LEDs and RGB LED
The kit has two user push buttons marked BTN0 and BTN1. They are connected directly to the ZGM230S and are debounced by RC
filters with a time constant of 1 ms. The buttons are connected to pins PB03 and PB02.
The kit also features two yellow LEDs marked LED0 and LED1 that are controlled by GPIO pins on the ZGM230S. The LEDs are con-
nected to pins PC08 and PC09 in an active-high configuration.
The kit has an RGB LED marked LED100, controlled by GPIO pins on the ZGM230S. The LED is connected in an active-low configura-
tion, and each color can be PWM controlled using the ZGM230S's TIMER peripherals to generate a wide variety of colors.
User Buttons
& LEDs
ZGM230S
RGBLED_G
RGBLED_B
BUTTON1
BUTTON0
PB03
PB02
PA00
PC04
PB01
RGBLED_R
PC08
PC09
LED0
LED1
Figure 3.11. Buttons and LEDs
UG532: ZGM230S Dev Kit User's Guide
Hardware
silabs.com
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