COPTONIX I2C-RS232-Adapter User manual

I2C RS232 Adapter
(SLAVE)
Manual
Luxemburger Str. 31
D – 13353 Berlin
Phone: +49 – (0)30 – 1 74 12 48
Fax: +49 – (0)30 – 1 74 12 47
www.coptonix.com
[e-mail]

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1. Description
The I2C-RS232-Adapter is a universal usable I2C to RS232 converter. With the
Adapter as I2C-Slave, several RS232 devices (e.g. PC, microcontroller) can be
connected to one I2C bus, or several I2C-Devices (Master) can be connected to one
RS232 device.
The slave address can be programmed freely over the serial interface. The default
slave address is 0 FE ( 1111 1110 ). The data of a master are temporarily stored in
the I2C-RS232-Adapter and then transmitted through the serial interface. A data
packet can be maximal 128 bytes.
The data, which a serial device receives (e.g. PC, microcontroller), can be processed
and then sent back to the I2C-RS232-Adapter. Here the data packet can be also
maximally 128 bytes. So that the I2C-RS232-Adapter can get the function of a
master, the I2C-RS232-Adapter controls two Interrupt outputs. An Interrupt output
can be selected over the serial interface while sending data to the adapter.
Two types of this adapter are available:
-I2C-RS232-Adapter RS (Part No. #020101):
This type is controlled only via the serial interface (RS232). The
communication is done through ASCII commands (see page 15).
-I2C-RS232-Adapter IC (Part No. #020102):
This type is controlled only via the I2C-Bus. The communication is done
through I2C commands (see page 8). The RS232 interface is transparent.
With the many possibilities of the Adapter it is very simple to define/program own
I2C-Slaves when connected to a PC or a microcontroller.
Therefore the adapter is suitable for developers, who would like to develop and/or
test own I2C-circuits. The Adapter can be a PCF8574, PCF8574A, temperature sensor
or any other slave with any (7-bit) slave address.
With a PC or microcontroller the Adapter can be used also to control devices with
I2C-Interface (Master). For software development, a Delphi component, a DLL,
examples and data transmission protocol of the Adapter are available for developer.
When using the software interfaces, the Adapter can be integrated very simply into
own applications

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2. Applications
2.1 One I2C-Master – multiple RS232 devices
I2C
-
RS232
-
Adapter (SLAVE)
Slave 2
I²C
-
Bus / 5V / GND
Slave 3
Slave 1
PC
Software
Slave ...
I2C- RS232-Adapter (SLAVE)
Micro-
Controller
RS232
RS232
I2C
MASTER

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2.1 Multiple I2C-Master – one RS232 device
Slave 2
I²C-Bus / 5V / GND
Slave 3
Slave 1
PC
Software
Slave ...
I2C
-
RS232
-
Adapter (SLAVE)
RS232
I2C
MASTER…
I2C
MASTER 2
I2C
MASTER 1

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3. Interface
• 1 RS232 port for communication with a PC (RxD, TxD, GND)
• 2 I²C-Interface
Pin 1: External pull-up voltage V
ext
(2V – 15V)
Pin 2: Supply voltage +5V
Pin 3: Ground
Pin 4: I2C – SCL
Pin 5: I2C –SDA
Pin : Interrupt – Output 1
Pin 7: Interrupt – Output 2
Header strip / 2.54 pitch
• 3 Jumper VUP – V
pull-up
Pull-up voltage
Pin 1: +3.3V
Pin 2: V
pull-up
; connected to pull-up resistors (4K7)
Pin 3: External pull-up voltage
Position 1-2: connects pull-up voltage to internal +3.3V
Position 3-2: connects pull-up voltage to external pull-up voltage.
• 4 LED Power-ON
1
2
3
4

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4. Dimension (mm)

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5. Characteristics
Min. Typ Ma . Unit
Power-Supply
Supply Voltage 5.0 V
Supply Current 12 15 mA
I2C-Bus pins (SCL, SDA)
V
ext
External Pull-up Voltage 2 - 15 V
V
IH
High-State Input Voltage 0.58V
pull-up
- - V
V
IL
Low-State Input Voltage - - 0.42V
pull-up
V
Limiting values
Interrupt pins
Input Voltage 0 - 5.5 V
Output Voltage 0 - V
DD(3,3V)
V
Power-Supply
Supply Voltage 4.0 5.0 .0 V
Temperature
operating temperature -20 - +70 °C

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6. I2C Commands (Only I2C-controlled devices / Part No. #020102)
6.1 Command Overview
Command Description Value
TransmitData Transmit data bytes (from I2C) over UART 0x74
ReadData Read data bytes received from UART 0x72
ReadCount Read count of received bytes (from UART) 0x 3
SetSlvAdr Set a new slave address to temporary register 0x41
ReadSlvAdr Read slave address from temporary register 0x42
SaveSlvAdr Save and initialise new slave address 0x43
SetBaud Set, save and initialise new baud rate 0x44
ReadBaud Read the currently adjusted baud rate 0x45
ResetBuffers Reset data buffers to initial state 0x
ReadVersion Read adapter’s version 0x7
SetUARTMode Set UART operation mode 0x4
GetUARTMode Get UART operation mode 0x47
SetETXChar Set UART ETX Character 0x48
GetETXChar Get UART ETX Character 0x49
SetTimeOut Set UART TimeOut 0x4A
GetTimeOut Get UART TimeOut 0x4B
6.2 Command Description
6.2.1 TransmitData
In order to transmit an array of data bytes (I2C -> UART) issue the following
command. The buffer size is limited to 128 bytes per message.
TransmitData command (0 74)
Byte Content Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
0 Slave Address A7 A A5 A4 A3 A2 A1 0
1 TransmitData 0 1 1 1 0 1 0 0
2 Data 1 1. data byte
… … 2. to n-1 byte
n+1 Data n n data byte (up to 128 data bytes)

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6.2.2 ReadData
This command is used for reading data that were received from UART and temporary
written into internal RAM.
ReadData command (0 72)
Byte content Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
0 Slave Address A7 A A5 A4 A3 A2 A1 0
1 ReadData 0 1 1 1 0 0 1 0
ReadData Response
Byte content Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
0 Slave Address A7 A A5 A4 A3 A2 A1 1
1 Slave Address Slave address of the selected device
2 Byte 1 1. Byte
… ... …
n+1 Byte n n Bytes (up to 128 bytes; n = Length)
When the adapter receives a message from UART, then output Pin5 is set low. This
Pin remains low until the ReadData command is issued, then Pin5 ist set high.
6.2.3 ReadCount
This command returns the number of bytes received from the UART interface.
ReadCount command (0 63)
Byte content Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
0 Slave Address (W) A7 A A5 A4 A3 A2 A1 0
1 ReadCount 0 1 1 0 0 0 1 1
ReadCount Response
Byte Content Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
0 Slave Address (R) A7 A A5 A4 A3 A2 A1 1
1 Slave Address Slave address of the selected device
2 Count Count of received bytes
3 Status x x x x x x x S
Status
0 Data already read S
1 New data packet
x Do not care

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6.2.4 SetSlvAdr
The default slave address is 0xFE (1111 1110). The “SetSlvAdr” command allows to
change the slave address of the adapter.
SetSlvAdr command (0 41)
Byte content Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
0 Slave Address A7 A A5 A4 A3 A2 A1 0
1 SetSlvAdr 0 1 0 0 0 0 0 1
2 Slave address Slave Address(7:1) 0
The new slave address is written to a temporary register and still not active. In order
to read/verify this new slave address, issue the command “ReadSlvAdr”. If the
command “SaveInitSlvAdr” is issued, then the new slave address is saved into the
EEPROM and the I2C-Interface is initialised.
6.2.5 ReadSlvAdr
read / verify the new slave address that was written to the temporary register.
ReadSlvAdr command (0 42)
Byte content Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
0 Slave Address (W) A7 A A5 A4 A3 A2 A1 0
1 ReadSlvAdr 0 1 0 0 0 0 1 0
ReadSlvAdr Response
Byte Content Bit 7
Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
0 Slave Address (R) A7
A A5 A4 A3 A2 A1 1
1 Slave Address Slave address of the selected device
2 New Slave Address New Slave Address (temporary register)
6.2.6 SaveInitSlvAdr
Save and initialize the new slave address.
SaveInitSlvAdr command (0 43)
Byte Content Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
0 Slave Address A7 A A5 A4 A3 A2 A1 0
1 SaveInitSlvAdr 0 1 0 0 0 0 1 1

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4.2.7 SetBaud
sets the baud rate of the UART.
SetBaud command (0 44)
Byte content Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
0 Slave Address A7 A A5 A4 A3 A2 A1 0
1 SetBaud 0 1 0 0 0 1 0 0
2 Baud Rate x x x x x Baud (2:0)
Baud
Bit2 Bit1 Bit0
Baud Rate
0 0 0 2400
0 0 1 4800
0 1 0 9 00
0 1 1 19200
1 0 0 28800
1 0 1 38400
1 1 0 57 00
1 1 1 115200
X (7:3) Do not care
4.2.8 ReadBaud
reads the currently adjusted baud rate.
ReadBaud command (0 45)
Byte content Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
0 Slave Address (W) A7 A A5 A4 A3 A2 A1 0
1 GetStatus 0 1 0 0 0 1 0 1
ReadBaud Response
Byte Content Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
0 Slave address (R) A7 A A5 A4 A3 A2 A1 1
1 Slave address Slave address of the selected device
2 Baud X X X X X Baud (2:0)

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4.2.9 ResetBuffers
deletes UART and I2C temporary RAM data.
SaveInitSlvAdr command (0 66)
Byte Content Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
0 Slave Address A7 A A5 A4 A3 A2 A1 0
1 ResetBuffers 0 1 1 0 0 1 1 0
4.2.10 ReadVersion
reads the version of the adapter.
ReadVersion command (0 76)
Byte Content Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
0 Slave Address (W) A7 A A5 A4 A3 A2 A1 0
1 ReadVersion 0 1 1 1 0 1 1 0
ReadVersion Response
Byte Content Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
0 Slave address (R) A7 A A5 A4 A3 A2 A1 1
1 Slave address Slave address of the selected device
2 FM_Version HIGH version HIGH Byte
3 FM_Version LOW version LOW Byte
e.g. 0x0102 => HiByte = 0x01 ; LoByte = 0x02
The version is read as a BCD code:
=> Version 01.02
4.2.11 SetUARTMode
sets the UART mode.
SetUARTMode command (0 46)
Byte content Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
0 Slave Address A7 A A5 A4 A3 A2 A1 0
1 SetUARTMode 0 1 0 0 0 1 1 0
2 UART Mode x x x x x x x M
UART Mode
0 TimeOut
Data received from the UART is forwarded to the I2C Output after a defined
time (milliseconds) is elapsed.
M
1 ETX Character
Data received from the UART is forwarded to the I2C Output after the ETX
character is detected.

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4.2.12 GetUARTMode
reads UART operation mode.
GetUARTMode command (0 47)
Byte Content Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
0 Slave Address (W) A7 A A5 A4 A3 A2 A1 0
1 GetUARTMode 0 1 0 0 0 1 1 1
GetUARTMode Response
Byte Content Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
0 Slave address (R) A7 A A5 A4 A3 A2 A1 1
1 Slave address Slave address of the selected device
2 UART Mode x x x x x x x M
6.2.13 SetETXChar
Sets a new End Of Text – Character, which triggers forwarding the received data to
the I2C output.
SetETXChar command (0 48)
Byte content Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
0 Slave Address A7 A A5 A4 A3 A2 A1 0
1 SetSlvAdr 0 1 0 0 1 0 0 0
2 ETX Character ETX Character(7:0)
6.2.14 GetETXChar
Reads End Of Text - Character.
GetETXChar command (0 49)
Byte content Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
0 Slave Address (W) A7 A A5 A4 A3 A2 A1 0
1 GetETXChar 0 1 0 0 1 0 0 1
GetETXChar Response
Byte Content Bit 7
Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
0 Slave Address (R) A7
A A5 A4 A3 A2 A1 1
1 Slave Address Slave address of the selected device
2 ETX Character ETX Character(7:0)

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6.2.15 SetUARTTimeOut
Sets UART’s timeout interval. TimeOut is the w ait time in milliseconds after receiving the
last character on the UART before the received data is forwarded to the I2C output.
SetUARTTimeOut command (0 4A)
Byte content Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
0 Slave Address A7 A A5 A4 A3 A2 A1 0
1 SetSlvAdr 0 1 0 0 1 0 1 0
2 TimeOut TimeOut Interval [ms] (7:0)
6.2.16 GetUARTTimeOut
Reads UART’s timeout interval.
GetUARTTimeOut command (0 4B)
Byte content Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
0 Slave Address (W) A7 A A5 A4 A3 A2 A1 0
1 GetUARTTimeOut 0 1 0 0 1 0 1 1
GetUARTTimeOut Response
Byte Content Bit 7
Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
0 Slave Address (R) A7
A A5 A4 A3 A2 A1 1
1 Slave Address Slave address of the selected device
2 TimeOut Timeout interval [ms] (7:0)

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7. ASCII Commands (Only RS232-controlled devices / #020101)
The data of an I2C master are temporarily stored and then transmitted through the serial interface. A data packet may be maximal
128 bytes.
I2CdataAvail 0x 9 i d
1
,d
2
,…d
128
’69’+’XXYYZZ….’+<CR> I2C-Data received from I2C-Master
<CR> : CarriageReturn (0x0D). Commands and data are always terminated with a Carriage Return.
*) ChangeSlaveAdress / GetSlaveAdress:
XX the Slave address.
e.g. in order to change the address to 0x40, we would send the following string terminated with a carriage return: ’c40’+<CR>
**) WriteData:
XXYYZZ... data to send to the adapter. Packet size is at least one byte and maximum 128 bytes.
Example: in order to write 5 Bytes 0xA1, 0x1F, 0x22, 0x5C, 0xB0 into RAM of the adapter, then the following string
(terminated with a carriage return) should be sent over the serial interface: ’wA11F225CB0’+<CR>
RS232 – Settings:
Baudrate: 19200
DataBits: 8
StopBits: 1
Parity: None
Code
Description
Command
He Char Parameter CMD + Data (->RS232) Response (<- RS232)
GetSlaveAddress* 0x 1 a ’a’+<CR> ’61’+’XX’+<CR> Read Slave address
ChangeSlaveAdress * 0x 3 c d
1
’c’+’XX’+<CR> ’63’+<CR> Change Slave Address
SaveSlaveAddress 0x73 s ’s’+<CR> ’73’+<CR> Save Slave address into EEPROM
WriteData ** 0x77 w d
1
,d
2
,…d
128
’w’+’XXYYZZ….’+<CR> ’77’+<CR> Write Data into RAM without Interrupt
WriteDataInt1 0x78 x d
1
,d
2
,…d
128
’ ’+’ XXYYZZ….’+<CR> ’78’+<CR> Write Data into RAM with Interrupt output 1
WriteDataInt2 0x79 y d
1
,d
2
,…d
128
’y’+’ XXYYZZ….’+<CR> ’79’+<CR> Write Data into RAM with Interrupt output 2