Raspberry Pi 3 for controlling olimex ice40HX8K (programming, JTAG, UART)

This document describes how to configure a Raspberry Pi 3 (Raspi) to program the lattice ice40HX8K fpga board from olimex (Oli).

Sources:

[1] olimex webiste, iceprog

[2] Using a Raspberry Pi as a JTAG Dongle

[3] Schematic Raspberry Pi 3B

[4] Schematic olimex iCE40HX9K-EVB

Preparing Rasperry Pi 3

1. format sd card with [sd memory card formatter] (https://www.sdcard.org/downloads/formatter_4/) 2.Download the NOOBS zip file, extract and put content on sd card
2. Insert card and boot raspberry pi 3
3. Login -> Default username: pi, password: raspberry
4. Enable ssh -> sudo raspi-config -> interface options -> enable ssh
5. Enable spi -> sudo raspi-config -> interface options -> enable spi

Cabeling

Power

The Raspi is powered with a 5V Micro USB cable The Oli is powered with a dedicated 5V power supply (alternatively the Olimex can be powered from the 5V of the Raspi)

Ground

The Grounds of the two boards need to be connected. See SPI.

SPI

We have to connect the following pins for SPI. Grounds are connected via this SPI connector.

Raspi Connector: J8
Oli Connector: PGM1

Raspi pin name/num	Oli pin name/num
SCK / 23	SCK / 9
MISO / 21	SDI / 7
MOSI / 19	SDO / 8
CE0 / 24	SS_B / 10
GPIO25 / 22	CDONE / 5
GND / 20	GND / 2
GPIO24 / 18	CRESET / 6

JTAG

We have to connect the following pins for JTAG. Reset is not unused.

Raspi Connector: J8
Oli Connector: GPIO1

Raspi pin name/num	Oli pin name/num
TCK / 35	TCK / 31
TMS / 36	TMS / 32
TDI / 37	TDI / 33
TDO / 38	TDO / 34
RST / 40	optional

UART

UART can be used to talk to the FPGA.

Raspi Connector: J8
Oli Connector: GPIO1

Raspi pin name/num	Oli pin name/num
Tx / 8	Rx / e.g. 28
Rx / 10	Tx / e.g. 27

Installation

For installing the tools run the script: sh install.sh

Programming

To prgram the FPGA run the script: program.sh programming_file.bin

The programming file can be generated with the yosys suite, see also SpinalDev).

JTAG Server

To start the openocd server run: openocd.sh

JTAG can be used to program and debug software (see for example SpinalDev)

UART

Make sure uart is enabled in the configuration (sudo raspi-config) and mincom is installed (sudo apt-get install minicom). Now access of uart may be done with:

minicom -b 115200 -o -D /dev/ttyAMA0