User Manual

More on Overrange and Overflow

Chapter 5

5–2

Each time an input for one (or more) of the channels is greater than 10.0

kHz, the overrange flag for that channel is set; for example, if the input

frequency for channel 1 is greater than 10.0 kHz, bit #4 is set. (This is the

first bit of the overrange group.)

Acknowledge Word = 1010 = 0001 XXXX XXX1 0000

Overrange, Channel 1

If the input frequency for any other channel is greater than 10.0 kHz, the

QRD sets the appropriate bit in the acknowledge code. It is possible for all

channels to be in an overrange condition; in such a case, the acknowledge

code would be:

Acknowledge Word = 10F0 = 0001 XXXX 1111 00000

All inputs are overrange (u10.0 kHz)

The overflow flags work in the same manner as the overrange flags. As an

example, when totalizer #1 has reached its maximum (32,767), an

overflow flag (bit #8) is set in the acknowledge code. If the acknowledge

code is put in binary format, it looks like this:

Acknowledge Code = 1100 = 0001 XXX1 XXXX 0000

Overflow, Channel 1

Any or all of the four channels can overflow, and any or all of the overflow

flags can be reset using a Block Transfer Write command. If all of the

channels overflow, the acknowledge code will look like:

Acknowledge Code = 1F00 = 0001 1111 XXXX 0000

All inputs are overflowed (u32,767)

Totalizer

Overflow Flags