configuration.md

HackEEG Configuration

These jumpers configure Arduino Due pins used on the HackEEG shield. For commonly-used settings, see Typical Configuration.

For ADS1299 pin definitions, refer to ADS1299 datasheet.

For Arduino Due pin definitions, refer to the Arduino Due pinout diagram, the Arduino Due reference, and the SAM3X8E datasheet.

If you change these jumpers, you must also change the pin definitions in your driver files. For the ads129x_tools driver, this is in the file adsCommand.h

Jumper Diagram

This diagram shows the locations of all the configuration jumpers:

Digital Configuration Jumpers

JP1 and JP2 – Board Connection

These pins select which ADS1299 pins are connected to which Arduino Due pins. Bridging one pair of jumpers connects the pins together. This enables a stack of shields to use different Arduino Due pins if needed, for instance to connect two HackEEG shields to the native SPI, and two to the USART1 SPI, or to use different Arduino Due PIO pins to control the ADS1299.

For each named signal, you must set exactly one jumper.

JP1 – Config0 – ADS1299 Control Configuration

Signal	Jumper #	Arduino pin
DRDY	1	D24
DRDY	2	D25
DRDY	3	D26
DRDY	4	D27
CLK	5	D30
CLK	6	D31
START	7	D61
START	8	D59
RESET	9	D46
RESET	10	D47
PWDN	11	D32
PWDN	12	D33

JP2 – Config1 – SPI Configuration

Signal	Port	Jumper #	Arduino pin
SPI MOSI	Native	1	SPI4
SPI MOSI	USART1	2	D16
SPI CS	Chip Select	3	D23
SPI CS	Chip Select	4	D52
SPI CS	Chip Select	5	D10
SPI CS	Chip Select	6	D4
SPI SCL	Native	7	SPI3
SPI SCL	USART1	8	A0
SPI MISO	Native	9	SPI1
SPI MISO	USART1	10	D17

Not configurable

These pins are hard-wired and cannot be configured.

Signal	Arduino pin
CLKSEL	D48
BOARD LED	ADS1299 GPIO4

JP3 – Board Address

These pins set the 24AA256 I2S EEPROM address 0-3 in binary – they are not connected to Arduino Due pins. The pins are shared with the ADS1299 GPIO, and so can also used as the board address and read via the ADS1299. If not using them as jumpers, external devices can be connected to the header to provide access to the ADS1299 GPIO pins; this usage generally will conflict with using the I2S EEPROM.

Jumper #	Function
0	ADS1299 GPIO0
1	ADS1299 GPIO1

Analog Configuration Jumpers

Instrumentation Power Supplies

These jumpers configure the instrumentation power supplies that supply the reference voltages for the ADS1299. You can set the ADS1299 to measure voltages in the 0–5V range (unipolar) or in the -2.5V – +2.5V range (bipolar). Bipolar is most commonly used for human or mammal subjects. You must bridge exactly one set of pins on each jumper.

JP 4

Pins	Function
1-2	Sets AVDD to 5V
2-3	Sets AVDD to 2.5V

JP 5

Pins	Function
1-2	Sets AVSS to -2.5V
2-3	Sets AVDD to GROUND

Common Settings

Mode Name	ADS1299 Voltage Range	JP4 Pins	JP5 Pins
Unipolar	0–5V	1-2	2-3
Bipolar	-2.5V – +2.5V	2-3	1-2

Stimulus-Response Buffer (SRB)

JP6 – SRB1 - BIAS

Pins	Function
1-2	Routes SRB1 to BIAS_ELEC on the electrode connector via a 5K resistor
2-3	Routes a noise source to SRB1
Unconnected	Disconnects BIAS from SRB1 – use in conjunction with JP7/JP8 REF_ELEC functions

Setting pins 2-3 can be used to test channel noise performance. See section 8.3 of the TI EEG Front-End Demonstration Kit manual. In this mode, BIAS_ELEC and REF_ELEC on the electrode connector need to be connected with a cable, since there is no jumper to do so on the HackEEG board.

JP7 – SRB1–REF_ELEC

Pins	Function
1-2	Routes SRB1 to REF_ELEC on the electrode connector via a 5K resistor
2-3	Routes SRB2 to SRB1 via an opamp

JP8 – SRB2–REF_ELEC

Pins	Function
1-2	Routes REF_ELEC on the electrode connector to the opamp input via a 5K resistor
2-3	Routes SRB2 to the opamp input

JP9 – BIASIN-BIASOUT-BIAS_ELEC

Pins	Function
1-2	Routes BIASOUT to BIAS_ELEC on the electrode connector via a 5K resistor
2-3	Routes BIASOUT to BIASIN
Unconnected	Leaves BIASOUT, BIASIN, and BIAS_ELEC unconnected