dCS 954 User Manual

Manual for Standard Software Version 1.5x

dCS Ltd

June 2000

Transmit -> [1][REQUEST_FS], request actual frequency Responds -> [ACK immediate][1], actual frequency

The system is now set up with the Master Clock configured for 96k operation and the ADCs and DACs locked in PCM mode to 96k.

Example: Switching to P3D

Change the Master Clock frequency to 44.1k prior to changing the ADC and DAC operating mode to DSD. Change the DAC operating mode prior to the ADC. When changing the Master Clock frequency the system should be allowed to settle to the new frequency before any further RS-232 activity.

6)Command Master Clock to change frequency. Allow the system time to settle after this command with no RS-232 activity, three seconds should be sufficient.

Transmit -> [1][SEL_FS], change to 44.1k Responds -> [ACK 3 seconds][1], requested frequency Wait for 3 seconds

7)Check Master Clock has changed frequency. If it has not go back to step 6.

Transmit -> [1][REQUEST_FS], request actual frequency Responds -> [ACK immediate][1], actual frequency

8)Command DACs 6, 7, 8 and 9 to change mode, the units may take up to 15 seconds to complete this command (if the previous mode had been PCM the FPGAs need to be re-loaded, which takes time). There is also no need to wait prior to moving on to step 9.

Transmit -> [6][DSD_MODE], to change mode to P3D of unit 6 Responds -> [ACK 15 seconds][6], requested mode Transmit -> [7][DSD_MODE], to change mode to P3D of unit 7 Responds -> [ACK 15 seconds][7], requested mode Transmit -> [8][DSD_MODE], to change mode to P3D of unit 8 Responds -> [ACK 15 seconds][8], requested mode Transmit -> [9][DSD_MODE], to change mode to P3D of unit 9 Responds -> [ACK 15 seconds][9], requested mode

9)Command ADCs 2, 3, 4 and 5 to change mode, the units may take up to 15 seconds to complete this command (if the previous mode had been DSD the FPGAs need to be re-loaded, which takes time). There is also no need to wait prior to moving on to step 10.

Transmit -> [2][DSD_MODE], to change mode to P3D of unit 2 Responds -> [ACK 15 seconds][2], requested mode Transmit -> [3][DSD_MODE], to change mode to P3D of unit 3 Responds -> [ACK 15 seconds][3], requested mode Transmit -> [4][DSD_MODE], to change mode to P3D of unit 4 Responds -> [ACK 15 seconds][4], requested mode Transmit -> [5][DSD_MODE], to change mode to P3D of unit 5 Responds -> [ACK 15 seconds][5], requested mode

10)Check DACs for mode change. This command allows the Transmitter to check the mode of the DACs. If a unit has not changed the transmitter should go back to step 8 and repeat the command.

Transmit -> [6][REQUEST_DSD_MODE] Response -> [ACK immediate][6], actual mode Transmit -> [7][REQUEST_DSD_MODE] Response -> [ACK immediate][7], actual mode

Manual part no: DOC136954 iss 2B1

Page 61

file 135954ma2b1.pdf available from website

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