Table of Contents
V-DIO EL502 EEPROM Programming
The newly manufactured EL502 Mezzanine cards do not contain any data in their EEPROM yet. A Raspberry Pi and a custom made cable are used to programm the EEPROM.
Resources
The code of this project is under version control in a Git repository whose upstream is: https://git.gsi.de/BEA_HDL/V_DIO_EEPROM_Programming
How to program the EEPROM
- connect the custom made cable to the Raspberry Pi and to the Mezzanine
- activate the I2C interface of the Raspberry Pi:
sudo raspi-config, browse toInterfacesand activate I2C - copy the
srcfolder to the Raspberry Pi or clone the Git repository on it
| Raspberry Pi | Raspberry Pi | Mezzanine | Mezzanine |
|---|---|---|---|
| pin number | signal name | pin number | signal name |
| 1 | +3.3 V | 1 | +5 V |
| 3 | SDA | 3 | SDA |
| 5 | SCL | 2 | SCL |
| 6 | GND | 26 | GND |
Programming with individual serial numbers
cd src./write_serial_number.py <serial number>
Alternative static programming and verification scripts
Programming
cd src./write_eeprom.py
This will program the content of src/eeprom_content.csv to the EEPROM.
Verification
cd src./read_eeprom.py
This will create an output file src/eeprom_content_readback.csv.
You can compare it to the desired content using diff eeprom_content_readback.csv eeprom_content.csv.
Testing the IO expanders
The six IO expanders on the EL502 Mezzanine can be accessed via the same I2C bus. The following commands can be used:
Listing the available I2C devices
i2cdetect -y 1 will list all available I2C devices on the I2C bus /dev/i2c-1
The output on the EL502 is the following:
0 1 2 3 4 5 6 7 8 9 a b c d e f
00: -- -- -- -- -- -- -- -- -- -- -- -- --
10: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
20: 20 21 22 -- 24 25 26 -- -- -- -- -- -- -- -- --
30: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
40: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
50: 50 -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
60: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
70: -- -- -- -- -- -- -- --
The devices with the addresses 0x20, 0x21, 0x22 are the IO expanders on the top side. The devices with the addresses 0x24, 0x25, 0x26 are the IO expanders on the bottom side. The device with the address 0x50 is the EEPROM.
Writing registers
Via single CLI accesses
E.g. i2cset -y 1 0x20 0x02 0xff will write the value of 0xff to the register 0x02 on the device with the I2C address 0x20.
Via a script
cd src./configure_io_expanders.py
This will program the content of src/io_expander_config.csv to the registers of the IO expanders.
Reading registers
Via single CLI accesses
E.g. i2cget -y 1 0x20 0x02 will read the value of the register 0x02 on the device with the I2C address 0x20.
Via a script
cd src./read_io_expanders.py
This will print all the register values of the IO expanders.