HI
I am looking for a device to test my SPI communication. (No, not a host device or slave simulator).
We have a product with a SPI master that talks to different products acting as slaves, using our own protocol.
To setup a regression test for the error detection on the master and slave devices, I need to inject errors on the SPI bus.
Note: This could be done by adding special features to the master and slave devices prompting them to send invalid telegrams, but that comes with a lot of additional SW maintenance, that I want to avoid.
Master -----------+------------Slave
^
|
Tester
So If master sends
0x12, 0x24, 0x53
and i ask the tester to inject 0xFF on second byte, what slave sees is this.
0x12, 0xFF, 0x53
or if i ask the tester to inject 1 on last bit in second byte, what slave sees is this.
0x12, 0x25, 0x53
Same functionality for slave to master.
I cold probably build this using an Arduino and a few resistors, and some clever SW, but I would prefer to buy something already done, as development time is money.
So does anybody know of a device to do this?
Edit: For the questions about length, the protocol running on our SPI, has a fixed length of 12 16-bit words = 192bit, for each telegram. And running at 7.5 Mhz.