EERAM
Iono RP D16 has a Microchip 47L16 16 Kbit SRAM with EEPROM Backup. This chip
combines the persistent storage characteristics of a traditional EEPROM, without the
limitations in terms of number of erase cycles. It is connected to the RP2040 I
2
C bus I2C0,
GPIO0 (SDA) and GPIO1 (SCL), address: 0x50 for the SRAM and 0x18 for the control
register.
ON LED control
The ON LED is normally on when the Iono RP D16 is powered, but it is also possible to
control it from the RP2040 using the SPI CS (chip select) lines, as shown in the circuit
diagram below. To turn the LED on or off, first set the SPI CS OUT D1-D8 line low or high,
then set both SPI CS IN D1-D8 and SPI CS IN D9-D16 low to latch the LED status. The
LED will remain in its on or off state until SPI CS IN D1-D8 and SPI CS IN D9-D16 are
again both set low to latch a new state.
ON LED CONTROL LINES
14
Iono RP D16 User Guide
