Target Electronics 27 th November 2008

Overview Current System is composed of many discrete units with separate processors that do not talk to each other. This comes about due to the modular design of the system. The current system was never really designed to be installed at ISIS due to the ‘expert’ nature of the system and the fact that it would not interface to a PC. Now that we have a functional but modular design it would be possible to integrate many of these functions -> this would give several advantages. – Smaller footprint – Better Resolution – Added Functionality and control

Overview Where functionality cannot be integrated it would be possible to connect the IC’s using the I 2 C protocol. All processors could then talk to a ‘master’ processor. The master processor could then orchestrate communication with the outside world. This protocol could not be implemented at the moment as there are not enough pins on the IC’s. Also some of those IC’s that are capable of I2C will have these pins tied up to other functions. NOT EASY TO CHANGE (IF AT ALL POSSIBLE) The added overhead would ideally require more powerful processors (move from 8 bit to 16 bit.) Certainly necessary where several functions are to be integrated onto one processor. As there is no way of directly communicating to the IC’s in the current control system it is not currently possible to pass values into the processors -> Therefore cannot control via an external computer.

Upgraded Electronics Overview Not only would parameters be able to be passed to the electronics but the electronics could also report back and this could be written to a log file of all system settings. Dated history of settings. (Could be used to instantly set parameters to a historical setting.) Error reporting Processor 1Processor 2Processor N Master ProcessorPC Network, USB, RS232

Functionality A carefully drawn up list of what we expect the target electronics to be able to do. (Note this is not the list!) – Bi-directional communication. – Addition of feedback mechanism to control the trajectory more carefully. Is this even required anymore based upon operational experience? – Addition of Improved Control System on Capture – Prevent Oscillations -> Reduce bearing wear. What else needs adding to this list? (Clearly needs some thought and detailed documentation before construction/development begins.)

Time-Scale It must be stressed that this is a significant upgrade. I 2 C protocol to be understood and established between processors. The mechanism/protocol by which the master talks to the PC must also be established, independently tested, code written. The algorithms on the current PIC’s will need porting over to the new processors. Code will need adding so that the processors can communicate with the master. Certain functionality could be integrated and this may offer control advantages. The more powerful processors do not lend themselves to veroboard construction. Proper PCB’s will need to be designed and manufactured. Estimate that this is at least a month project. This is a project that I very much would like to take on. (But will need assistance on the electronics/PC interface)