OLIMEX MOD-IO User manual

MOD-IO
Open-source hardware UEXT extension board with relays and
USER’S M NU L
Document revision C, May 2020
Designed by OLIMEX Ltd, 2014
All boards produced by Olimex LTD are ROHS compliant

OLIMEX© 0 0 MOD-IO user's manual
DISCL IMER
© 0 0 Olimex Ltd. Olimex®, logo and combinations thereof, are registered trademarks of Olimex Ltd. Other product names
may be trademarks of others and the rights belong to their respective owners.
The information in this document is provided in connection with Olimex products. No license, express or implied or
otherwise, to any intellectual property right is granted by this document or in connection with the sale of Olimex
products.
This work is licensed under the Creative Commons Attribution-ShareAlike 3.0 Unported License. To view a copy of this
license, visit http://www.creativecommons.org/licenses/by-sa/3.0/.
This hardware design by Olimex LTD is licensed under a Creative Commons Attribution-ShareAlike 3.0 Unported License.
The part of the example software that was written by Olimex is released under GPL. If there are parts of the software
belonging to other developers or companies they maintain their respective rights of the code.
It is possible that the pictures in this manual differ from the latest revision of the board.
The product described in this document is subject to continuous development and improvements. All particulars of the product
and its use contained in this document are given by OLIMEX in good faith. However all warranties implied or expressed
including but not limited to implied warranties of merchantability or fitness for purpose are excluded. This document is
intended only to assist the reader in the use of the product. OLIMEX Ltd. shall not be liable for any loss or damage arising
from the use of any information in this document or any error or omission in such information or any incorrect use of the
product.
This evaluation board/kit is intended for use for engineering development, demonstration, or evaluation purposes only and is
not considered by OLIMEX to be a finished end-product fit for general consumer use. Persons handling the product must have
electronics training and observe good engineering practice standards. As such, the goods being provided are not intended to be
complete in terms of required design-, marketing-, and/or manufacturing-related protective considerations, including product
safety and environmental measures typically found in end products that incorporate such semiconductor components or circuit
boards.
Olimex currently deals with a variety of customers for products, and therefore our arrangement with the user is not exclusive.
Olimex assumes no liability for applications assistance, customer product design, software performance, or infringement of
patents or services described herein.
THERE IS NO W RR NTY FOR THE DESIGN M TERI LS ND THE COMPONENTS
USED TO CRE TE MOD-IO. THEY RE CONSIDERED SUIT BLE ONLY FOR MOD-IO.
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Table of Contents
DISCL IMER ..................................................................................................................... 2
CH PTER 1: OVERVIEW ................................................................................................ 5
1. Introduction to the chapter ................................................................................................................ 5
1.1 Features .............................................................................................................................................. 5
1.2 Target market and purpose of the board ........................................................................................ 5
1.3 Board variants ................................................................................................................................... 6
1.4 Board version used in the manual ................................................................................................... 6
1.5 Document organization ..................................................................................................................... 6
CH PTER 2: SETTING UP THE MOD-IO BO RD ..................................................... 7
2. Introduction to the chapter ................................................................................................................ 7
2.1 Electrostatic and electrical polarity warning .................................................................................. 7
2.2 Hardware requirements .................................................................................................................... 7
2.3 Software requirements ...................................................................................................................... 8
2.4 Powering the board ........................................................................................................................... 8
2.5 Changing the firmware ..................................................................................................................... 9
2.6 Connecting more than one MOD-IO together ................................................................................ 9
2.7 Default firmware description ......................................................................................................... 10
2.7.1 Setting relays ............................................................................................................................................................ 10
2.7.2 Getting the state of opto-isolators ........................................................................................................................... 11
2.7.3 Reading the value of an analog input ..................................................................................................................... 12
2.7.4 Changing the I2C address of a board .................................................................................................................... 13
2. 8 rduino with MOD-IO ................................................................................................................... 14
2. 9 OLinuXino boards with MOD-IO ................................................................................................. 14
CH PTER 3: MOD-IO BO RD DESCRIPTION ........................................................ 16
3. Introduction to the chapter .............................................................................................................. 16
3.1 Layout (top view) ............................................................................................................................. 16
CH PTER 4: THE TMEG 16 MICROCONTROLLER ....................................... 17
4. Introduction to the chapter .............................................................................................................. 17
4.1 The processor ................................................................................................................................... 17
CH PTER 5: CONNECTORS ND PINOUT .............................................................. 19
5. Introduction to the chapter .............................................................................................................. 19
5.1 Communication with MOD-IO ...................................................................................................... 19
5.2 VRISP connector ........................................................................................................................... 20
5.3 JT G connector ............................................................................................................................... 20
5.4 EXT ................................................................................................................................................... 21
5.5 UEXT_M LE .................................................................................................................................. 22
5.6 UEXT_FEM LE ............................................................................................................................. 22
5.7 Digital inputs, digital outputs and analog inputs ......................................................................... 22
5.7.1 IN1, IN2 IN3, IN4 – digital inputs with opto-isolators ......................................................................................... 23
5.7.2 OUT1, OUT2, OUT3, OUT4 – digital outputs ...................................................................................................... 23
5.7.3 IN-1 and IN-2 – analog inputs ........................................................................................................................... 23
5.8 PWR jack ......................................................................................................................................... 24
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5.9 dditional hardware components .................................................................................................. 24
CH PTER 6: SCHEM TICS .......................................................................................... 25
6. Introduction to the chapter .............................................................................................................. 25
6.1 Eagle schematic ............................................................................................................................... 25
6.2 Physical dimensions ......................................................................................................................... 27
CH PTER 7: REVISION HISTORY ND SUPPORT ................................................. 28
7. Introduction to the chapter .............................................................................................................. 28
7.1 Document revision ........................................................................................................................... 28
7.2 Board revision .................................................................................................................................. 28
7.3 Useful web links and purchase codes ............................................................................................. 29
7.4 Product support ............................................................................................................................... 30
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CH PTER 1: OVERVIEW
1. Introduction to the chapter
Thank you for choosing the MOD-IO extension module from Olimex! This document provides a user’s
guide for the MOD-IO board. As an overview, this chapter gives the scope of this document and lists the
board’s features. The document’s organization is then detailed.
The MOD-IO board allows easy expansion of the functionality of other boards by adding relays,
optocouplers and analog inputs.
MOD-IO is an open-source, open-hardware project and all documentation is available to the customer.
1.1 Features
The board has the following set of features:
•Open source hardware board with ATMega16L-8AU microcontroller
•4-optocoupler isolated inputs with screw terminals
•Input status LEDs
•4-relay outputs with 5A/ 50VAC contacts with screw terminals
•Output status LEDs
•Stackable
•ICSP 5× pin connector for in-circuit programming with AVR-ISP500 and AVR-ISP-MK or
another compatible ICSP programmer
•JTAG 5× pin connector for in-circuit programming with AVR-JTAG, AVR-JTAG-USB or
another compatible JTAG debugger
•EXT extension connector for the unused AVR ports
•Status LED
•Reset IC ZM33064
•Quartz crystal oscillator circuit 8MHz
•DC-DC with input voltage 8-30VDC – this board can be powered from 4V industrial power
supplies
•Power plug-in jack
•Four mounting holes 3.3 mm (0.13")
•FR-4, 1.5 mm (0.06 "), red soldermask, white silkscreen component print
•Dimensions 80×100 mm (3.9×3.15")
1.2 Target market and purpose of the board
The Olimex boards that carry the “MOD-” prefix in their product name are typically extension boards
with a UEXT connector. They are usually used to expand the functions of a “host board” (another board
with main microcontroller of its own and UEXT connector).
UEXT is a board to board connector which supports three serial communication interfaces – I C, SPI and
RS 3 . It is a great way to expand the features of the development boards you already have. The
customer can choose which new feature he wants to expand. More on the UEXT might be found in the
following document:
https://www.olimex.com/Products/Modules/UEXT/resources/UEXT_rev_B.pdf
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MOD-IO provides 4 relays with proper connector that allow the switching of circuits. The board is also
equipped with 4 optocouplers (also known as opto-isolators) that transfer electrical signals between two
isolated circuits by using light. MOD-IO also has 4 analog inputs won a connector.
MOD-IO comes with built-in firmware which makes the usage of the board's peripherals much easier. It
uses a standard I C communication and several commands are defined. The source of the firmware is also
available to the customer.
Customers have full access to the technical documentation of the board. The software is released under
General Purpose License and the board is considered open-hardware – all schematics and board design
files are available to the customer under the Creative Commons Attribution-ShareAlike 3.0 Unported
License.
1.3 Board variants
A smaller variant of the MOD-IO board is the MOD-IO one. It has relays (compared to the 4 of the
MOD-IO) and uses Microchip's PIC16 microcontroller (compared to the Atmel's ATmega16).
MOD-IO is also stackable and again comes with custom firmware for easier start. It uses I C for
communication.
MOD-IO is also a completely open design – hardware files and firmware sources are available to the
customer.
1.4 Board version used in the manual
Hardware revision A1 boards and resources were used while writing this document. It is possible that they
are not the same hardware revision at your side so it is always recommended to download the latest
sources from the product page of the board
(https://www.olimex.com/Products/Modules/IO/MOD-IO/open-source-hardware).
1.5 Document organization
Each section in this document covers a separate topic, organized as follows:
–Chapter 1 is an overview of the board usage and features
–Chapter provides a guide for quickly setting up the board and software notes
–Chapter 3 contains the general board diagram and layout
–Chapter 4 describes the component that is the heart of the board: the ATmega16A microcontroller
–Chapter 5 covers the connector pinout, peripherals and jumper description
–Chapter 6 provides the schematics and the dimensions of the board
–Chapter 7 contains the revision history, useful links and support information
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CH PTER 2: SETTING UP THE MOD-IO BO RD
2. Introduction to the chapter
This section helps you set up the MOD-IO extension development board for the first time. Please consider
first the electrostatic warning to avoid damaging the board, then discover the hardware and software
required to operate the board.
The procedure to power up the board is given, and a description of the default board behavior is detailed.
2.1 Electrostatic and electrical polarity warning
MOD-IO is shipped in a protective anti-static package. The board must not be exposed to high
electrostatic potentials. A grounding strap or similar protective device should be worn when handling the
board. Avoid touching the component pins or any other metallic element.
When connecting other electrical devices to the MOD-IO board make sure that they have equal electrical
polarity. This usually occurs in setups where you need to use more than one power supply unit. If you
have such a setup make sure different power supplies are connected to the same electrical source (to the
same utility power socket).
In rare cases different polarity might cause hardware damage to one of the boards in your setup.
2.2 Hardware requirements
In order to set up the MOD-IO optimally one or more additional items may be used. They might be
generally placed in three categories:
Required – items that are needed in order to achieve minimum functionality;
Recommended – items that is good to have in order to be able to interact with the most important of the
features of the board;
dditional – items that provide access to additional features or expand the features of the board.
Required items:
- Power supply unit that is able to provide (6V- 0V) C or (8V-30V) DC
Recommended items:
- An ISP programmer or a JTAG debugger – if you wish to modify the firmware you would need a way to
upload the binary code to the board; in case you wipe the memory accidentally or you need to replace the
main microcontroller you would also need such a tool.
Please note that Olimex has a few low-cost programmers supported by both Atmel studio and
AVRDUDE.
dditional items include:
- Jumper cables – comes in handy when you want to connect something to the MOD-IO or when you
want to measure a hard to reach spot
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Some of the above-suggested items can be purchased by Olimex, for instance:
VR-ISP500 – an STK500-compatible low-cost programmer, compatible with Atmel Studio 6 or any
previous version; also compatible with AVRDude
VR-ISP-MK2 – an open-source programmer based on ISP-MKII, compatible with Atmel Studio 6 or
any previous version; also compatible with AVRDude
VR-ICSP – an adapter 6<->10 pin AVR ISP
SY0612E – reliable power supply adapter 50Hz (for EU) 1 V/0.5A for A10-OLinuXino-LIME
SY0612E-CHIN – cheaper power supply adapter 50Hz (for EU) 1 V/0.5A for A10-OLinuXino-LIME
2.3 Software requirements
Olimex provides the sources of the firmware built-in MOD-IO. The project was created and compiled
with AVR studio 4
In order to edit the firmware you would need to set up an AVR environment.
AVR studio and Atmel studio are typically used. They are supported by Atmel and free-to-use. The
environments are not considered open-source, however.
Alternatively, there are a number of open-source tools that can be used – the most popular programmer
being AVRDude. There are a lot of tutorials on how to configure a Linux environment for AVR. Please
note that setting such a working development environment under Linux might be a quite a time-
consuming task.
2.4 Powering the board
The only way to power the board is to provide sufficient voltage and current to the PWR_J connector.
The owner of the board has to provide either AC or DC voltage to board. The AC voltage has to be in the
6V to 0V range. The DC voltage has to be in the 8V to 30V range.
The typical consumption of MOD-IO with the default firmware and no additional peripherals connected
and no relays turned on is as follows:
0.0 A @ 8V DC;
0.0 A @ 16V DC;
0.01A @ 30V DC.
After the board is powered the red PWR_LED would turn on and yellow STAT LED would start blinking.
The behavior of the STAT LED is determined by the firmware/software on the board.
For the European customers we sell two power supply adapters, please check chapter . .
Note that it is normal that when the board is powered some integrated circuits might appear hotter than
others. This is perfectly normal for some chips – for instance – voltage regulators and the main processor.
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2.5 Changing the firmware
In order to change the firmware of MOD-IO you would need an ISP programmer or a JTAG debugger.
Such tools might be purchased from various sources including Olimex. If you are in doubt whether a tool
would work with MOD-IO you should ensure that:
1. the tool supports the main microcontroller AVR ATmega16A
and
. the tool has either 10-pin JTAG connector or 10-pin ISP connector (or you would need to use jumper
wires or adapter)
As already mentioned in chapter “ .3 Software requirements” to edit the original firmware you would
need AVR Studio 4, since this is the integrated development environment we used. At some point you
might decide to add own keywords and behavior that suits your project better than what we have done.
Of course, you can decide to completely skip this part and use the board as a general-purpose AVR board.
You can write own software or firmware from scratch.
2.6 Connecting more than one MOD-IO together
If you need more than 4 relays or more than 4 optocouplers you might connect another MOD-IO board
since each board has both male and female UEXT connectors and the communication protocol is I C – it
allows multiple devices on the same bus – each addressed by a unique identifier. You may plug the boards
directly – the UEXT_FEMALE connector of the first MOD-IO would plug in the UEXT_MALE
connector of the second MODIO.
You can connect more than two boards this way.
Note that if you want to use more than one MOD-IO on the same I C bus you would need to change the
built-in the firmware identifier. Each board needs a unique address. There is a command to change
discussed in the next chapter – “ .6 Default firmware description”.
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2.7 Default firmware description
The demo is built-in each MOD-IO board. The source code might be found in the software section at the
product page at our web site. Direct link to the board's web-page:
https://www.olimex.com/Products/Modules/IO/MOD-IO/resources/MOD-IO.pdf
Direct link to the latest firmware:
https://www.olimex.com/Products/Modules/IO/MOD-IO/resources/MOD-IO(I C-Slave)_v1.0 .zip
The archive with the sources contains a prebuilt binary which also might be used to restore the initial
functionality. The project was compiled with AVR studio 4 and WinAVR compiler (available at
sourceforge.net).
The demo requires an established hardware I C connection between the module and a host board. You
would need to send and receive parameters to the slave device to be able to communicate with the
following peripherals on the board:
- Digital outputs (relays): OUT1, OUT , OUT3, OUT4 – signals: O1, O , O3, O4.
- Digital inputs (optocouplers): IN1, IN , IN3, IN4 – signals: I1, I , I3, I4.
- Analogue inputs: AIN-1- , AIN-1-3, AIN- -1, AIN- - – signals AN1, AN , AN3, AN4.
There is nothing specific about the I C protocol. Default address of the slave is 0b1011000 (0×58). When
addressed, the device acknowledges reception with an ACK flag set to 0 to indicate its presence. After
connection is established you can use additional commands, detailed below.
2.7.1 Setting relays
Set states of the digital outputs on the board. The board features four relay outputs named OUT1, OUT ,
OUT3 and OUT4 that can be set together with one command. The command should have the following 3
byte format:
************************************
S aaaaaaaW cccccccc 0000dddd P
************************************
,where
S – start condition
aaaaaaa – slave address of the board
W – write mode, should be 0
cccccccc – command code, should be 0×10
dddd – bitmap of the output states, i.e. bit0 corresponds to REL1, bit1 to REL and so on. '1'
switches the relay ON, '0' switches to OFF state.
P – Stop condition
Example:
To set REL1 and REL3 in pseudo code:
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i cStart(); //Send start condition
i cSend(0xb0); //This is 0x58 shifted to left one time and added 0 as W
i cSend(0x10); //Command to set relays
i cSend(0x05); //0x05 → 0b00000101 → This way we will set REL1 and REL3
i cClose(); //Send stop condition
2.7.2 Getting the state of opto-isolators
The board features four optoisolated inputs named IN1, IN , IN3 and IN4 and their statuses can be read
together with one command. The command should have the following format:
************************************
S aaaaaaaW cccccccc P S aaaaaaaR 0000dddd P
************************************
,where
S – start condition
aaaaaaa – slave address of the board
W – write mode, should be 0
cccccccc – command code, should be 0× 0
P – Stop condition
R – read mode, should be 1
dddd – bitmap of the input states received from the MOD-IO board, i.e. bit0 corresponds to IN1,
bit1 to IN and so on. '1' means that power is applied to the optocoupler, '0' means the opposite.
Note: Successive readings from the board without reissuing the command code will not get an updated
value of the ports (i.e. the user will read the same value) until another command is issued.
Example:
Reading optocoupled inputs in pseudo code
i cStart() //Send start condition;
i cSend(0xb0); //This is 0×58 shifted to left one time and added 0 as W
i csend(0x 0); //Read inputs commands
i cClose(); //Send stop condition
i cStart(); //Send start condition. You can use i cRestart() instead
i cSend(0xb1); //This is 0×58 shifted to left one time and added 1 as W
byte = i cRead(); //Read one byte of data;
i cClose();
/* “byte” now holds the state of the inputs. To “decode” bitmask the data. */
in1 = byte & 0x01; //To get state of IN1
in = byte & 0x0 ; //To get state of IN
in3 = byte & 0x04; //To get state of IN3
in4 = byte & 0x08; //To get state of IN4
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2.7.3 Reading the value of an analog input
Get the voltage applied to one of the analogue inputs of the board. The board features four 10bit
resolution analogue inputs (input voltages from 0 – 3.3V) and each of them is read with a separate
command. Command should have the following common format:
************************************
S aaaaaaaW cccccccc P S aaaaaaaR dddddddd 000000dd P
************************************
,where
S – start condition
aaaaaaa – slave address of the board
W – write mode, should be 0
cccccccc – command code, should be 0×30 for AIN1, 0×31 for AIN , 0×31 for AIN3, 0×31 for
AIN4.
P – Stop condition
R – read mode, should be 1
dddddddd 000000dd – Little Endian (LSB: MSB) 10bit binary encoded value corresponding to the
input voltage. Range is 0 – 0×3FF and voltage on the pin is calculated using the following simple
formula: voltage = (3.3 / 10 4) * (read value) [Volts]
Note: Successive readings from the board without reissuing the command code will not get an updated
value of the voltage (i.e. the user will read the same value) until another command is issued.
Example:
Reading AN1 in pseudo code:
i cStart(); //Send start condition
i cSend(0xb0); //This is 0×58 shifted to left one time and added 0 as W
i cSend(0x30); //Read analog value of IN1
i cStop(); //Send stop condition
i cStart(); //Send start condition. You can use i cRestart() instead
i cSend(0xb1); //This is 0×58 shifted to left one time and added 1 as W
l_byte = i cRead(); //Read the low 8 bits of the ADC reading
h_byte = i cRead(); //Read the high bit of the ADC reading
i cStop(); //Send stop condition
/* Since l_byte is (LSB:MSB) we need to convert it to (MSB:LSB). To swap bits one by one do
the following */
analog = 0;
for(int index = 0; index < 8; index++){
analog |= ((l_byte & 0x80) ? 1 : 0) << index;
l_byte <<= 1;
}
/* Now add the high bit to the value */
analog |= ((h_byte & 0x0 ) ? 1 : 0) << 8;
analog |= ((h_byte & 0x01) ? 1 : 0) << 9;
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/* To convert digital reading to voltage use this */
voltage = (analog*3.3)/10 3;
2.7.4 Changing the I2C address of a board
Sets new slave address to the board. The board ships with default 7bit address 0×58 that can be changed
to any other 7bit value in order for the host to interface more than 1 device connected on the bus at the
same time. Change is stored in EEPROM and thus is permanent between power cycles. Changing the
address requires the following command format:
************************************
S aaaaaaaW cccccccc 0ddddddd P
************************************
,where
S – start condition
aaaaaaa – slave address of the board (the default or the old address of the board)
W – write mode, should be 0
cccccccc – command code, should be 0xF0
ddddddd – new 7bit address to update
P – Stop condition
NB!! To protect the device from accidental address updates the user should hold the on-board button
pressed (not the RESET button!) while issuing the command. Successful update is indicated with the on-
board status LED being contently lit for -3 seconds. Address is immediately updated so the board will
not respond to its old address any more.
IMPORTANT: The default address of the board could be restored if the on-board button is held pressed at
power up for more than 4 seconds. This situation is indicated by the on-board LED blinking fast for the
timeout period. When the fast blinking ends default address is restored.
Example:
Change address to 0× in pseudo code:
i cStart(); //Send start condition
i cSend(0xb0); //This is 0×58 shifted to left one time and added 0 as W
i cSend(0xF0); //Command to change address
i cSend(0x ); //New address
i cClose(); //Send stop condition
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2.8 rduino with MOD-IO
We provide a ready-to-use library for Arduino IDE with an example code for turns on and off all relays of
MOD-IO. The code also allows the reading and printing of all digital inputs and all analog inputs over the
serial monitor. In order to set it up first download the archive from the link below:
https://www.olimex.com/Products/Modules/IO/MOD-IO/resources/MOD-IO-ARDUINO.zip
1. Extract the archive, copy and paste the folder "MOD-IO" into the "libaries" folder of your Arduino
IDE.
. Start Arduino IDE
3. To load the example, navigate to File → Examples → MOD-IO → RELAYS-INPUTS
4. Remember to select your board and the COM port it uses for communication.
5. The demo uses serial communication, it is recommended to use the serial monitor in Arduino IDE (it
can be started from Tools → Serial Monitor).
The example was tested with OLIMEXINO-3 8 and MOD-IO with I C address 0x58.
Refer to the comments inside the example for more information
2.9 OLinuXino boards with MOD-IO
You can connect MOD-IO to all OLINUXINO boards that have UEXT connector. Connect the two
boards using UEXT cable. After that boot the default Debian and use the program called “i c-tools”. If it
is missing enter the following commands in the console of your OLINUXINO board to obtain it:
# apt-get update
# apt-get install i c-tools
To set all relays use:
# i cset -y -f 0x58 0x10 0x0F
,where:
i cset – the part of i c-tools that is used to for sending data over the i c;
-y – skips confirmation;
-f – specifies the number of the I C bus used; test with values “1” or “ ”;
0x58 – the I C address of the board that we want to send data to;
0x10 – the command to set relays (different commands have different code, refer to chapter .6 of
this manual);
0x0F – the state of relays is stored in the 4 least significant bits of the binary representation of
0x0F → 0b00001111 → affecting all 4 relays (other example → 0x05 → 0b00000101 →
affects relays 1 and 3).
To turn off all relays use:
# i cset -y -f 0x58 0x10 0x0F
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To read digital inputs:
# i cget -y -f 0x58 0x 0 c
To read analog value of IN1:
# i cset -y -f 0x58 0x30
# i cget -y -f 0x58 w
To change address to 0× :
# i cset -y -f 0x58 0xF0 0x
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CH PTER 3: MOD-IO BO RD DESCRIPTION
3. Introduction to the chapter
Here you get acquainted with the main parts of the board. Note the names used on the board might differ
from the names used below to describe them. For the actual names check the MOD-IO board itself.
3.1 Layout (top view)
The picture below shows the top side of the board and highlights the most important parts:
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CH PTER 4: THE TMEG 16 MICROCONTROLLER
4. Introduction to the chapter
In this chapter is located the information about the heart of OLinuXino – its microcontroller. The
information is a modified version of the datasheet provided by its manufacturers.
4.1 The processor
MOD-IO uses an 8-bit AVR microcontroller with 16K Bytes In-System Programmable Flash, with these
features:
High-performance, Low-power AVR® 8-bit Microcontroller
Advanced RISC Architecture
131 Powerful Instructions – Most Single-clock Cycle Execution
3 ×8 General Purpose Working Registers
Fully Static Operation
Up to 16 MIPS Throughput at 16 MHz
On-chip -cycle Multiplier
High Endurance Non-volatile Memory segments
16K Bytes of In-System Self-programmable Flash program memory
51 Bytes EEPROM
1K Byte Internal SRAM
Write/Erase Cycles: 10,000 Flash/100,000 EEPROM
Data retention: 0 years at 85°C/100 years at 5°C
Optional Boot Code Section with Independent Lock Bits
In-System Programming by On-chip Boot Program
True Read-While-Write Operation
Programming Lock for Software Security
JTAG (IEEE std. 1149.1 Compliant) Interface
Boundary-scan Capabilities According to the JTAG Standard
Extensive On-chip Debug Support
Programming of Flash, EEPROM, Fuses, and Lock Bits through the JTAG Interface
Peripheral Features
Two 8-bit Timer/Counters with Separate Prescalers and Compare Modes
One 16-bit Timer/Counter with Separate Prescalers, Compare Mode, and Capture Mode
Real Time Counter with Separate Oscillator
Four PWM Channels
8-channel, 10-bit ADC
8 Single-ended Channels
7 Differential Channels in TQFP Package Only
 Differential Channels with Programmable Gain at 1x, 10x, or 00x
Byte-oriented Two-wire Serial Interface
Programmable Serial USART
Master/Slave SPI Serial Interface
Programmable Watchdog Timer with Separate On-chip Oscillator
On-chip Analog Comparator
Special Microcontroller Features
Power-on Reset and Programmable Brown-out Detection
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Internal Calibrated RC Oscillator
External and Internal Interrupt Sources
Six Sleep Modes: Idle, ADC Noise Reduction, Power-save, Power-down, Standby and
Extended Standby
I/O and Packages
3 Programmable I/O Lines
Operating Voltages
.7 – 5.5V
Speed Grades
0 – 8 MHz
Power Consumption @ 1 MHz, 3V, and 5 C⋅
Active: 1.1 mA
Idle Mode: 0.35 mA
Power-down Mode: < 1 µA
More information can be found on Microchip's web site at the following web-address:
http://ww1.microchip.com/downloads/en/devicedoc/atmel-8154-8-bit-avr-atmega16a_datasheet.pdf
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OLIMEX© 0 0 MOD-IO user's manual
CH PTER 5: CONNECTORS ND PINOUT
5. Introduction to the chapter
In this chapter are presented the connectors that can be found on the board all together with their pinout
and notes about them. Jumpers functions are described. Notes and info on specific peripherals are
presented. Notes regarding the interfaces are given.
5.1 Communication with MOD-IO
There are several ways for communication with MOD-IO and its main microcontroller ATMEGA16A.
The three typical communication routines are: via I C by utilizing the default firmware; via ISP with a
compatible programmer tool and writing own code; via JTAG with a compatible debugger tool and
writing own code.
The communication with the board's default firmware is performed typically via the I C line that might
be found on the UEXT connector. For more information on how the default firmware might be accessed
please refer to chapter .6.
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5.2 VRISP connector
The AVRISP connector is used to program the board. You can plug a standard ISP programmer (which
has a 10-pin connector) to it. Make sure your programmer supports the programming of ATMEGA16A
microcontroller. Almost any ISP programmer would be capable of programming the chip. OLIMEX sells
at least two programmers suitable for the board – they are named AVR-ISP500 and AVR-ISP-MK – both
working fine with all versions of Atmel Studio and also open source tools like AVRDude. Both have 10-
pin ISP connector.
If your programmer has only 6 pin interface you can still use it for programming as long as you make a
small adapter or set jumper wires properly. Tables with proper connections required to convert 6-pin ISP
to 10-pin ISP are seasy to be found. You can also use our adapter AVR-ICSP:
https://www.olimex.com/Products/AVR/Programmers/AVR-ICSP/
The pinout of AVRISP might be found below:
Pin # Signal name
1 MOSI
2 3.3V
3 NC
4 GND
5 RST
6 GND
7 SCK
8 GND
MISO
10 GND
5.3 JT G connector
The JTAG connector is used to program the board. You can plug a standard ISP programmer (which has a
10-pin connector) into it. Make sure your programmer supports the programming of ATMEGA16A
microcontroller. Almost any ISP programmer would be capable of programming the chip.
Pin # Signal Name
1 TCK
2 GND
3 TDO
4 3.3V
5 TMS
6 RST
7 3.3V
8 NC
TDI
10 GND
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