Raspberry Pi Forums

will the astro pi be stackable with other boards? eg. a motor control and power board

as it has cool features that could be usefull on a robot

Yes it will be. The ones that will fly will be in a stack themselves, we have an RTC board which goes on first and then the Astro Pi goes on top. This is because the Pi isn't allowed on the ISS LAN (not for this mission anyway) and would have no means of getting the time from NTP etc.

All the kids will just have the Astro Pi HAT on it's own though.

Davespice wrote:Yes it will be. The ones that will fly will be in a stack themselves, we have an RTC board which goes on first and then the Astro Pi goes on top. This is because the Pi isn't allowed on the ISS LAN (not for this mission anyway) and would have no means of getting the time from NTP etc.

All the kids will just have the Astro Pi HAT on it's own though.

Ah... I've seen the statements about the AstroPi HAT planned to go into general production and availability, but what about whatever HAT you're using for the RTC? Will that be available?

Davespice wrote:The ones that will fly will be in a stack themselves, we have an RTC board which goes on first and then the Astro Pi goes on top.

In the original blog post (http://www.raspberrypi.org/astro-pi/) it mentions that the Astro-Pi HAT will have a real time clock with backup battery. Has this been changed now so that the RTC is no longer on the Astro-Pi HAT but on a seperate RTC HAT?

W. H. Heydt wrote:Ah... I've seen the statements about the AstroPi HAT planned to go into general production and availability, but what about whatever HAT you're using for the RTC? Will that be available?

The RTC we're using is a PCF8523 and you're welcome get one yourself. The RTC board we've made (we're not calling it an official HAT) is a one off just for the mission and there are no plans to make it generally available. But when you write your code for the competition you can just assume that the system clock time will be correct and accurate when your code runs in space.

ryan88 wrote:In the original blog post (http://www.raspberrypi.org/astro-pi/) it mentions that the Astro-Pi HAT will have a real time clock with backup battery. Has this been changed now so that the RTC is no longer on the Astro-Pi HAT but on a seperate RTC HAT?

Correct yes. The Engineers were unable to fit everything onto the Astro Pi sense HAT due to physical space constraints so the RTC board (we're not calling it an official HAT) is there to house the RTC chip, the coin cell battery holder and the crystal. It will only be used for the Astro Pis that get flown to the ISS.

Davespice wrote:Yes it will be. The ones that will fly will be in a stack themselves, we have an RTC board which goes on first and then the Astro Pi goes on top. This is because the Pi isn't allowed on the ISS LAN (not for this mission anyway) and would have no means of getting the time from NTP etc.

All the kids will just have the Astro Pi HAT on it's own though.

My company is developing a "host" for PIs that would be housed in Nanoracks modules that would interface with the ISS LAN. We look forward to the results of the 2 PIs at ISS, although we are looking at supporting Rev 2 PIs, and ultimately a powered Ethernet connection.

I'm thinking of getting a WittyPi to be stacked along with the Astro Pi. The WittyPi has an RTC and a power management system that allows the Pi to be started up using a push button or according to a script with a schedule. According to the makers of the WittyPi (www.uugear.com), the HAT uses the GP2 and GP3 pins for I2C communication (with a fixed address 0x68), GP4 and GP17 for operational features (can be changed to 2 other ports), and GP14 to inform it if the system is shutdown.

Given this, can I stack Astro Pi on top of the WittyPi? I searched the Internet for any information on the GPIO pins that Astro Pi uses but couldn't get any information apart from that it uses I2C as the communication channel. Any help will be greatly appreciated.

Davespice wrote:Yes it will be. The ones that will fly will be in a stack themselves, we have an RTC board which goes on first and then the Astro Pi goes on top. This is because the Pi isn't allowed on the ISS LAN (not for this mission anyway) and would have no means of getting the time from NTP etc.

All the kids will just have the Astro Pi HAT on it's own though.

sarathchandars wrote:I'm thinking of getting a WittyPi to be stacked along with the Astro Pi. The WittyPi has an RTC and a power management system that allows the Pi to be started up using a push button or according to a script with a schedule. According to the makers of the WittyPi (http://www.uugear.com), the HAT uses the GP2 and GP3 pins for I2C communication (with a fixed address 0x68), GP4 and GP17 for operational features (can be changed to 2 other ports), and GP14 to inform it if the system is shutdown.

Given this, can I stack Astro Pi on top of the WittyPi? I searched the Internet for any information on the GPIO pins that Astro Pi uses but couldn't get any information apart from that it uses I2C as the communication channel. Any help will be greatly appreciated.

Schematic here: https://www.raspberrypi.org/wp-content/ ... T-V1_0.pdf

jdb wrote:Schematic here: https://www.raspberrypi.org/wp-content/ ... T-V1_0.pdf

jdb, many thanks for the schematic. I figured that the 3 pins that are used by Witty Pi (7, 8, 11) are free and hence part of the questions has been answered. Since Sense HAT also uses I2C can you help with the address that is configured or is it configured to assign an 'available' address? For instance, Witty Pi has a fixed address of 0x68.