Electro-Voice 250, 1252 operation manual Communication

9.8.2: Communication

Maximum registers per request, read or write, is 4 registers.orm

The device will operate with the following Default Mode Parameters. See section 9.4.1 for details.

Address	247 (F7H)
Baud Rate	57600 Baud
Transmit Delay Time	20 csec

9.8.3: Normal Mode

Energy readings are given to the device frequently. The device generates a pulse at each channel after a certain energy increase.

Normal Operation consists of three processes:

1.The first process accepts writes to registers 04097 - 04112. Writes can be up to four registers long and should end on the fourth register of a group (register 04100, or registers 04103-04112 or registers 04109-04112). These writes can be interpreted as two-byte, four-byte, six-byte or eight-byte energy readings. The reception of the first value for a given channel provides the initial value for that channel. Subsequent writes will increment the Residual for that channel by the difference of the old value and the new value. The previous value is then replaced with the new value. Attempting to write a value greater than the programmed Rollover Value for a given channel is completely ignored and no registers are modified. If the difference is greater than half of the programmed Rollover Value for a given channel, the write does not increment the Residual but does update the Last Value. Overflow of the Residual is not prevented.

2.The second process occurs in the main loop and attempts to decrement the Residual by the Programmed Energy/Pulse Value. If the Residual is greater than the Programmed Energy/Pulse Value and the Pending Pulses Value for that channel is not maxed, then Residual is decremented appropriately and the Pending Pulses is incremented by two, signifying two more transitions and one more pulse.

3.The third process runs from a timer which counts off pulse widths from the Programmable Minimum Pulse Width Values. If there are Pulses Pending for a channel and the delay has passed, then the Pulses Pending is decremented for that channel and the Output Relay is toggled.

Operation Indicator (0000H = OK, 1000H = Problem):

Bit 1: 1 = EEPROM Failure

Bit 2: 1 = Checksum for Communications Settings bad

Bit 3: 1 = Checksum for Programmable Settings bad

Bit 4: 1 = 1 or mor Communications Settings are invalid

Bit 5: 1 = 1 or more Programmable Settings are invalid

Bit 6: 1 = 1 or more Programmable Settings have been modified

Bit 7: 1 = Forced Default by Reset Value

Bit 15: 1 = Normal Operation of the device is disabled

Electro Industries/GaugeTech Doc # E107706 V1.25 9-14