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SLOW CONTROLS FOR CMS DRIFT TUBE CHAMBERS

M. Bellato, L. CastellaniINFN Sezione di Padova

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2M. Bellato, L. Castellani INFN - Padova

DT SLOW CONTROLS (DTSC)

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3M. Bellato, L. Castellani INFN - Padova

DTSC COMPONENTS –1

• CONTROL BOARD– Close to DTBX chambers– Housed in cooled minicrates– Microprocessor based– External world I/F via serial

optical link(s)

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4M. Bellato, L. Castellani INFN - Padova

DTSC COMPONENTS - 2

• SERIAL LINKS– One direct link from each

control board to counting room

– One direct link from half wheel control board to counting room

– One daisy chained link from sector collector to control boards (half wheel)

– One local link for maintenance

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5M. Bellato, L. Castellani INFN - Padova

DTSC COMPONENTS - 3

• SLOW CONTROL MASTER– Sits in the

counting room

– 250 RS232 optical connections

– Houses the DCS interface

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6M. Bellato, L. Castellani INFN - Padova

CONTROL BOARD FUNCTIONALITY

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7M. Bellato, L. Castellani INFN - Padova

DTCCB - GOAL

•Clock distribution•Test Pulse signals distribution•Distribution and Readout of analog signals•Distribution and Readout of control signals•Temperature monitoring•Trigger Board and Readout Board ASICs setup and housekeeping

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8M. Bellato, L. Castellani INFN - Padova

DTCCB – CLOCK DISTRIBUTION

• 40 MHZ LHC clock(s) via a TTCrx chip

• Low skew ( < 1ns) clock tree network to Trigger Boards, Server Boards and Readout Boards

• Decoding of TTC signals

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9M. Bellato, L. Castellani INFN - Padova

DTCCB – Test Pulse Signals Distribution

• Programmable test pulse generation during orbit gap via TTC TEST signal

• Only orthogonal tracks• Programmable delay

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10M. Bellato, L. Castellani INFN - Padova

DTCCB - Distribution and Readout of analog signals

• One 8 inputs ADC and one DAC

• Monitor of Power Supply lines for front-end boards

• Monitor of Power Supply lines for minicrate boards

• Readout of pressure values in the chamber

• Set of operational parameters in the front-end boards (threshold, bias,…)

• Readout of various temperatures in the chamber and in the minicrate

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11M. Bellato, L. Castellani INFN - Padova

DTCCB – Distribution and Readout of control signals

• On/Off to different boards and to sections of the board itself

• 3 I2C ports for front-end boards, RPC and alignment system

• Voltage regulators FAULT signal detection

• Test pulse sequence control

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12M. Bellato, L. Castellani INFN - Padova

DTCCB – ASICs Interface

• JTAG I/F for programming the Trigger Board and Readout Board

• Independent JTAG chains for the Trigger Board and Readout Board

• 4 bit addressable JTAG bus (max. 16 boards)

• Fast Parallel I/F for accessing Trigger Board (e.g. loading of lookup tables, etc..)– Shares the Trigger

Data Path

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DTCCB LAYOUT

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COMMUNICATION CHANNELS

• Optical asynchronous RS232 channel to each control board

• Four-fibre cables connect two minicrates each

• Daisy-chained RS485 channel for each half wheel– RS485 -> RS232

conversion done on Sector Collector Control Board

– Backup communication channel

• Local RS232 port for service and maintenance

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15M. Bellato, L. Castellani INFN - Padova

SLOW CONTROL MASTER –1

• 250 asynchronous RS232 optical channels

• Software flow control• Deep transmit and

receive fifos– Increase latency– Decrease interrupt

rate to crate controller

• DCS Interface

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16M. Bellato, L. Castellani INFN - Padova

SLOW CONTROL MASTER –2

Choice of technology– CompactPCI

• One 6U crate with 21 slots or two 6U crates with 10 slots

• 16 boards with 16 ports each• Optical connectors both on

front and rear side• Requires an intelligent

controller– Might run a diskless OS

(VxWorks, LynxOS,..)– Might run Win NT/2k with

DCS stuff• Might be operated with an

MXI controller from a PC

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17M. Bellato, L. Castellani INFN - Padova

SOFTWARE

Needed :• Firmware for Control Board

– Only a very preliminary version exists– A basic version under development at CIEMAT

• Software driver for RS232 Uarts on the Slow Control Master

• Bridge for communicating with SCADA control systems

• DCS Interface

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18M. Bellato, L. Castellani INFN - Padova

STATUS

• Control board– Few prototypes working– Final version expected in Q2 2002 (TTCrx delay)

• Serial connections– Choice of optical transceivers done– 600 pieces procured (Q4 2001)

• Slow Control Master– Choice of technology done– First board prototype being assembled now

• Software– Very preliminary version of CCB firmware existing– UART driver not existing– SCADA bridge available from DCS people– DCS interface not existing