1. What is “Control System” or “Framework”?
General purpose of control system
need to control a lot of equipment from remote

2. What is “Control System” or “Framework”?
We need a “Network” to connect instruments and controller

3. Small system
In case the number of target instruments are limited, simple program can do everything. This is true for small laboratory.

4. Control Framework
We need a control framework in case many instruments, programs, developers, operators, .... Tight communication and organic linkage between components are required.

5. If we want to add a “New” instument
Need same “Language” and “Communication Protocol” with existing environment.

6. In reality
Commercial product does not support EPICS or Tango frame-work in many cases. We need to develop support them.

7. IOC (Input/Output Controller) manage hardware
In case of EPICS
IOC (Input/Output Controller) manage hardware
IOC: VME, PC, PLC, software, etc...
Need special code depends on each device
CPU
IOC PC
PLC
VME, cPCI
CAMAC, etc
DIO
DIO
DAC
ADC
RS232C
GPIB, etc
Field Busses
Device
Device
Target
Device
Device
Device
Device

8. EPICS : Communication
Need to communicate with standard protocol between presentation layer and IOC layer.
Presentation Layer : Server process, Archiver, GUI, etc
Independent from each device
Operator Console
Presentation
Server
Archive
Operator Console
Operator Console
Network
CPU
IOC PC
PLC
VME, cPCI
CAMAC, etc
DIO
DIO
DAC
ADC
RS232C
GPIB, etc
Field Bus
Device
Device
Target Dev.
Device
Device
Device
Device

9. EPICS : Communication Protocol
Channel Access protocol (PV, Process Variable)のやりとりをする
Network transparent. Distributed system.
CA protocol is used between IOCs
Operator Console
Presentation
Server
Archiver
Operator Console
Operator Console CA
Ethernet CA
CPU
IOC PC
PLC
VME, cPCI
CAMAC, etc
DIO
DIO
DAC
ADC
RS232C
GPIB, etc
Field Busses
Device
Device
Target Dev.
Device
Device
Device
Device

10. When you buy an instrument on the market
If the device has an embedded ioc, we have nothing to do! CA
EPICS IOC embedded Device
Ethernet
Just power on, plug to the network, and the instruments speak/listen CA protocol
In reality, very few instuments understand EPICS or Tango. Accelerator research is very small field on the market.

11. for example : RS232C device
Media converter (RS232C  Ethernet) are often used
Need to put media converter near to the device
Distance between IOC and Device can be very long CA
Socket
IOC
Media Converter
Device
Ethernet
Ethernet
USB
RS232, RS422, RS485, etc
Socket protocol are used between IOC and M.C.
“Steam Device”

12. Example commercial product
Serial-Ethernet Converter (Media Converter)
RS232
M.C.
Device
Socket
RS485
PC/IOC
M.C.
Device
Device
Device
Device
M.C.
Device
Ethernet
Device
Many company produces similar product.
So many variety of the price and functionality.
2, 4, 8, 16 port, etc.
Photo from

13. EPICS + Media Converter
soft IOC on the server computer.
IOC is a kind of “Protocol Converter”
Logical Description
Physical Description
Linux Server
CA Client
Software IOC
Socket I/O
Stream Device
DB Access
Channel Access
IOC Database CA
Ethernet
Socket I/O
Stream Device
DB Access
Channel Access
IOC Database
IOC
CA Client
Socket CA
Ethernet
Socket
Ethernet
Serial-Ether Conv.
Serial-Ether Conv.
RS232C Device
RS232C Device

14. Disadvantage of the media converter
Tend to increase network traffic
You need to mange a session between IOC and media converter.
For example: Initialize Socket protocol, reconnect, etc
You don’t need to care for CA protocol. (already defined)
Linux Server
Software IOC
Socket I/O
Stream Device
DB Access
Channel Access
IOC Database
CA Client
Socket CA
Session Management
Ethernet
(depends on the device)
Traffic
Serial-Ether変換
not a problem for slow serial.
RS232C Device

15. not an ideal solution, but better than media converter
We want a “small” device server attached to the device CA
Device Server
Device
Ethernet
USB
RS232, etc

16. Comparison of configurationCA
Client
EPICS IOC embedded Device A)
Ethernet CA
Client
IOC Device Server
Device B)
Ethernet
USB
RS232, etc CA
Socket
Client
IOC
Media Converter
Device C)
Ethernet
Ethernet
USB
RS232, etc CA
Socket
Client
IOC
Device D)
Ethernet
Ethernet

17. wait... Is there any differences between Linux PC and Device Server?
Basically no difference
Price, Size, Power consumption, TCO (Total cost of ownership), etc
Hardware support for long time
Consider these requirement to select the base hardware CA CA
Ethernet
Ethernet
Linux PC
Device Server
RS232, USB, PCI board etc
RS232, USB, etc
Device
Device
Device
Device
Device
Device

18. Candidates Credit-Card size board Arduino BeagleBone Black
Raspberry Pi (model B)
Raspberry Pi (model B+)

19. Candidates (1) [RasPi 3 is not listed in this table]
BeagleBone Black(Rev.C)
Raspberry Pi
(ModelB)
Arduino Uno
CPU
TI AM3359
(ARM Cortex-A8)
Broadcom BCM2835
(ARM11)
Atmel ATMega 328
Speed
1 GHz
700 MHz
16 MHz
RAM
512MB
512MB
2 KB
Storage
Onboard eMMC 4GB
microSD slot
32 KB Flash
I/O(GPIO) 65 8 20
ADC 7
n/a
Ethernet
10/100 x1 OS
Debian(default)
Angstrome Linux
Fedora etc
Raspbian(Debian)
Pidora(Fedora)
ARCH linux etc
Size [mm]
86.4 x 53.3
85.6 x 54
75 x 53.3
Price
\ 6,500
\ 3,940
\ 3,024