Sigma manual C4 Manual Rev

byte 01 (status byte replica), the first 32 bytes (256 bits) are “event triggered”. The second 32 bytes (256 bits) are “status” or “state set”.

Except for bits 0, 1 & 2 of the byte 01 (status byte replica), each of the bits in bytes 0-31 are set once when the condition that that bit reports becomes true. If the condition becomes false, the bit remains set. Except for bits 0, 1 & 2 of the byte 01 (status byte replica), the bits in bytes 0-31 are all reset in the event of a QE or QEA command, a system reset, or a power off condition.

Each of the bits in bytes 32-63 are set when the condition that the bit reports becomes true and is reset if that condition becomes false. The bits mirror the instantaneous state of the condition that they report. These bits are not reset by the event of a QE or QEA command, but are reset during system reset or power off condition.

Each of the bytes in the Error/Status String has a defined purpose. For instance, all the probe correction error bits are in the same byte. This makes is easier to parse the Error/Status String and branch to error routines because basic groups of errors can be checked at the byte level.

Note: Byte 00 of the Error/Status String is the same Error Byte that is available using RE and REA commands. Byte 00 is cleared each time a QE or QEA command is issued. This byte is also cleared anytime the RE or REA commands are issued to read the Error Byte. This byte is maintained in the Error/Status String so that it is not necessary to use two commands to obtain the Error Byte and the extended error information contained in the Error/Status String.

Byte 01 of the Error/Status String is the same as the EIA-232 version of the Status Byte. The bits 3 & 4 are cleared from both the Status Byte and byte 01 of the Error/Status String when the Error/Status String is read.

Many of the bits in the Error/Status String have no current definition and will always be reset (0). Each successive release of Sigma Systems C4 controller firmware may implement additional bit definitions. Each new list will be backward compatible. The length of the Error/Status String will remain at 64 bytes. The table below shows the firmware release in which the bit was first used and the definitions for the currently defined bits.

78 C4 Manual Rev 7.5.2