ZBasic Application Note AN-218 Video

Here is a video of the sample application supplied with ZBasic application note AN-218. The messages are transmitted at 9600 baud which makes the sequence easily visible but not too slow.

First of all identify all of the components on the breadboard:

• ZX-24ae acting as Master (top right) with red power LED
• ZX-24ae acting as Slave (top middle) with red power LED and green LED to mark completion
• Master RS-485 header (far right) with red transmit LED
• Slave RS-485 header (middle)
• Serial to USB connection to host PC - connected to Slave TX/RX/ATN
• Master debugging via MAX232 transceiver chip to host PC (far left). Note the red wire across the top of the picture which is connected to logical COM4 on pin 14 (D.6) of the Master ZX-24ae.

1. Master talks to slave 1 (red LED flash on RS-485 header far right) but no response
2. Master talks to slave 2 (red LED flash on RS-485 header far right) and Slave responds (red LED flash on RS-485 header in middle and green flash on ZX-24ae).
   • repeats 9 more times
3. Green light comes on for Slave to signal completion
4. Master talks to slave 3 (red LED flash on RS-485 header far right) but no response
   • repeats 4 more times for slaves 4 through 7
5. Master completes cycle and notes at least one change by lighting its green LED
6. Master pauses for 2 seconds
7. Master starts again and extinguishes the green LED
8. Master talks to each of the remaining 6 slaves (red LED flash on RS-485 header far right) but no response
9. No change in slave status so green LED in Master is not lit.

Click on picture to play the video.