I/O Expander with Real Time Clock for the Raspberry Pi with prototyping area.

(click on image for larger version – shown assembled & tested, sold as a kit)

Pi Rtc Dio adresses the two most desired additions for the Raspberry Pi

32 additional digital I/O

Real Time clock

Due to the limited current available from the Raspberry Pi’s 3.3v rail, Pi Rtc Dio also provides on-board voltage regulation from the Pi’s 5V supply to 3.3V, allowing up to 600mA to be drawn.

Pi Rtc Dio Features

32 bit I/O expander (2x MCP23017)

up to four Pi Rtc Dio’s per Raspberry Pi (selectable address)

optional Real Time Clock (PCF8563, only one per Pi)

optional 3.3V power regulation

I2C expansion header

hcomm header

four 10 pin headers for Mikronauts modules

large prototyping area

Software Compatibility

WiringPi MCP23017 extension module

WiringPi GPIO utility

i2ctools

Linux kernel module for PCF8563 RTC

Python libraries available

(click on image for larger version – blank printed circuit board photo)

Pi Rtc Dio supports the following configurations:

“Gold” (Fully populated)



32 bits I/O

Real Time Clock

3.3V voltage regulation

“Silver” (RTC section not populated)



32 bits I/O

3.3V voltage regulation

“Bronze” (RTC and voltage regulation not populated)



32 bits I/O

Rtc (only RTC parts)



Real Time Clock

A single Raspberry Pi can mount one “Gold” and up to three additional “Silver” or “Bronze” Pi Dio’s.

In addition, “Bronze” Pi Dio’s do not need to be stacked on top of the Raspberry Pi, but may be connected to any Mikronauts board that stacks on top of the Raspberry Pi with a simple four wire I2C cable.

(click on image for larger version – shown assembled & tested, sold as a kit)

If you have any questions about Pi Rtc Dio, please visit our forums at https://forums.mikronauts.com

Downloads & Documentation

To buy samples, please look for our Ebay listings.

Pi Rtc Dio is available immediately.

Pi Rtc Dio “Gold” Kit: $29.95USD + s/h (Full Kit)



includes printed circuit board

all parts for the I/O expanders

all parts for RTC section

all parts for 3.3v power regulation

Pi Rtc Dio “Silver” Kit: $24.95USD + s/h (NO RTC)



includes printed circuit board

all parts for the I/O expanders

all parts for 3.3v power regulation

Pi Rtc Dio “Bronze” Kit: $19.95USD + s/h (NO RTC, NO 3.3V regulation)



includes printed circuit board

all parts for the I/O expanders

Pi Rtc Kit: $15.95USD + s/h (NO DIO, NO 3.3V regulation)



includes printed circuit board

all parts for RTC section (NO DIO expansion, no voltage regulation)

Pi Rtc Dio PCB Specifications:

ROHS and Lead Free

FR4 ENIG 1-oz copper

85mm * 56mm

mounting holes matching those on the Raspberry Pi

Related Products for the Raspberry Pi

Shipping & Handling

Please contact us for non-US shipping rates for your desired product mix and quantity

for one only Pi Rtc Dio Kit s/h is $8.00USD to the continental US, no insurance, no tracking

for 2-3 Pi Rtc Dio kits s/h is $16.50 to the continental US, $100 insurance, tracking number provided (Tracked Small Packet)

Larger orders will ship Expedited Parcel, tracked, insured to order value – please inquire for exact shipping rate for your desired order.

Please contact me for shipping quotes for other destinations or for a larger number of kits with your address, as for larger quantities I use “Expedited Post” for which I need the destination and number of kits. At three kits and up, Expedited ends up costing less on a per-kit basis than the options above.

Shipping to Canada is somewhat cheaper (as Mikronauts based in Canada), shipping outside of North America costs more.

Quantity pricing is available for distributors and educational organizations.