Tibbo Device Servers ("DS") feature two status LEDs*- Status Red (SR) and Status Green (SG)- that display various states of device operation. DS states are indicated by way of playing "LED patterns". Patterns in this topic are represented graphically in the following manner:
The pattern above means that both green and red status LEDs blink together three times. The following pattern means that red LED makes one long blink followed by two short ones:
When the Monitor is running status LEDs display a number of conditions:
 | Slow-blinking Green Status LED means that the serial upgrade was completed successfully. |
 | Slow-blinking Red Status LED means that there was a timeout while waiting for the XMODEM data. If this happens right in the beginning of the serial upgrade then most probably this is caused by incorrect serial settings on the PC side, incorrect serial cable wiring, or incorrect XMODEM start procedure- XMODEM must be started on the PC first, and only then the DS is switched on (with he Setup button pressed). |
 | Communications error. This pattern means that an error was detected on the protocol level in XMODEM communications. Most often this means that incorrect communications parameters are set on the PC side. |
 | Firmware file is too big. This pattern means that the file you are trying to upload into the DS is too big. Check if you have selected a correct file. |
 | FLASH failure. This pattern means that internal FLASH memory of the DS is malfunctioning. |
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