Hardware/CubeSat RPi

(Difference between revisions)
Jump to: navigation, search
(Board to board)
Line 6: Line 6:
 
and a Microsemi [https://www.microsemi.com/product-directory/fpgas/1690-proasic3 ProASIC3]
 
and a Microsemi [https://www.microsemi.com/product-directory/fpgas/1690-proasic3 ProASIC3]
 
[[:File:ProASIC3E.pdf|M1A3PE3000-2FG484I]] FPGA.
 
[[:File:ProASIC3E.pdf|M1A3PE3000-2FG484I]] FPGA.
 +
 +
= Connectors =
 +
 +
== Board to board ==
 +
 +
The inter-board connection is a serial bus with coaxial cables for Tx and Rx lines.
 +
These channels are duplified for reasons of security.
 +
To this comes a 0 V, a 3.3 V and 5 V power supply.
 +
 +
The connection is done by coaxial connectors on two board sides.
 +
 +
== Raspberry Pi to FPGA ==
 +
 +
All Raspberry Pi I/O lines are connected to the FPGA.
 +
xxx of them are connected to the FPGA programming lines.
 +
 +
= Programming =
 +
 +
The Raspberry Pi Zero loads its operating system from the SD card.
 +
 +
The FPGA can be programmed either from the JTAG connector or from the Raspberry Pi.
 +
One has to make sure that the lines on the Raspberry Pi connector are tri-stated when trying to program the FPGA.
  
 
= Power supplies =
 
= Power supplies =
  
The board is powered from a standard 5 V ± 5% (4.75 V to 5.25 V).
+
The board is powered from a standard 5 V ± 5% (4.75 V to 5.25 V)
 +
as defined for USB.
 +
An additional 5 V can be supplied too.
  
 
This power supply is used by:
 
This power supply is used by:
* the Raspberry Pi which generates a 3.3 V for itself and for the FPGA I/O banks
+
* the Raspberry Pi which generates a 3.3 V for itself
* a DC/DC converter which generates a 1.5 V for the FPGA core
+
* a DC/DC converter which generates a 1.5 V for the FPGA core from the 5 V power supply
 +
 
 +
The RPi 3.3 V can be used for the FPGA I/O banks through a 0 Ω resistor
 +
if there is no 3.3 V power from the inter-board connector.
  
 
The FPGA is supplied with:
 
The FPGA is supplied with:
Line 37: Line 64:
 
| VPUMP || programming supply || style="text-align:right" | 3.3 V
 
| VPUMP || programming supply || style="text-align:right" | 3.3 V
 
|}
 
|}
 
= Connectors =
 
 
== Board to board ==
 
 
The inter-board connection is a serial bus with coaxial cables for Tx and Rx lines.
 
These channels are duplified for reasons of security.
 
To this comes a 0 V, a 3.3 V and 5 V power supply.
 
 
The connection is done by coaxial connectors on two board sides.
 
 
== Raspberry Pi to FPGA ==
 
 
All Raspberry Pi I/O lines are connected to the FPGA.
 
xxx of them are connected to the FPGA programming lines.
 
 
= Programming =
 
 
The Raspberry Pi Zero loads its operating system from the SD card.
 
 
The FPGA can be programmed either from the JTAG connector or from the Raspberry Pi.
 
One has to make sure that the lines on the Raspberry Pi connector are tri-stated when trying to program the FPGA.
 

Revision as of 13:49, 6 December 2019

Contents

This board is to serve an easy to use demonstrator for a CubeSat On-Board Computer (OBC). It hosts a Raspberry Pi Zero and a Microsemi ProASIC3 M1A3PE3000-2FG484I FPGA.

Connectors

Board to board

The inter-board connection is a serial bus with coaxial cables for Tx and Rx lines. These channels are duplified for reasons of security. To this comes a 0 V, a 3.3 V and 5 V power supply.

The connection is done by coaxial connectors on two board sides.

Raspberry Pi to FPGA

All Raspberry Pi I/O lines are connected to the FPGA. xxx of them are connected to the FPGA programming lines.

Programming

The Raspberry Pi Zero loads its operating system from the SD card.

The FPGA can be programmed either from the JTAG connector or from the Raspberry Pi. One has to make sure that the lines on the Raspberry Pi connector are tri-stated when trying to program the FPGA.

Power supplies

The board is powered from a standard 5 V ± 5% (4.75 V to 5.25 V) as defined for USB. An additional 5 V can be supplied too.

This power supply is used by:

  • the Raspberry Pi which generates a 3.3 V for itself
  • a DC/DC converter which generates a 1.5 V for the FPGA core from the 5 V power supply

The RPi 3.3 V can be used for the FPGA I/O banks through a 0 Ω resistor if there is no 3.3 V power from the inter-board connector.

The FPGA is supplied with:

Name function voltage
GND ground 0 V
GNDQ quiet ground 0 V
VCOMPLA/B/C/D/E/F PLL ground 0 V
VCC core supply 1.5 V
VCCIBx I/O supply 3.3 V
VMVx quiet I/O supply 3.3 V
VCCPLA/B/C/D/E/F PLL supply 1.5 V
VJTAG JTAG supply 3.3 V
VPUMP programming supply 3.3 V
Personal tools
Namespaces
Variants
Actions
Navigation
Browse
Toolbox