User manual

C hwtest
C.11. All-in-one Test for Alena
It is possible to test all serial ports, CAN and GPIO without reattaching the cables. Following
components will be needed to make such a test:
• modified USB cable for USB-CAN (see Figure 34) so that GND and VCC wires will switched
through relays and the outer GND is also isolated
• modified null-modem cable to connect PORT2, PORT4 and USB-CAN together (see Figure
33). Ports 1 and 3 will be connected with the same cable but without connector for USB-CAN
• special board for GPIO tests, that connects optically isolated inputs to bidirectional channels
(see Figure 35)
• special --canprod flag must be activated to use this features
VCC
GND
D-
D+
DO7-B
DO7-C
DO6-B
DO6-C
The outer GND must be isolated
Figure 34: Modified USB cable


  
 


 
 
 






Figure 35: Special Board for GPIO Tests
Connect all components as described above. With the following command GPIO, CAN and serial
tests will be executed:
hwtest --cycles=2 --size=4096 --can --canspeed=20000 --canprod --serial --seri=/dev/ttyS2
--sero=/dev/ttyS4 --gpio --io --poll
CAN test must be executed with low speed like 20000 bit/s, because the cable has no termination
resistors. All other tests can be made without further modifications.
May 2014 OnRISC User Manual 81