The Fx1616-BA has 4 MOSFETs that drive OUTPUTS 5,6,7 and 8. These can be used to drive 2 stepper motors using external driver boards. This is fact and well documented.
In order to use Stepper Channel #2 to drive OUPUTS 7 and 8, i-TRiLOGI the ch argument must be 32 to access the stepper channel for the following TBASIC statements:
- StepMove 32, count, r
- StepMoveAbs 32, count, r
The following TBASIC functions and statements will accept either "32" and "2" as the "ch" argument and execute on real hardware as expected:
- StepCountAbs(32)
- StepCountAbs(2)
- StepCount(32)
- StepCount(2)
- StepSpeed 32, pps, acc
- StepSpeed 2, pps, acc
The "odd man out" is the StepStop statement. The i-TRiLOGI complier will accept both "StepStop 2" and "StepStop 32". When running on Fx1616BA hardware, "StepStop 32" does not abort the current motion command . "StepStop 2" does abort the current motion command.
The online help does suggests that legal values of "ch" are 1..8. This is not true of any PLC that you have manufactured, yet. There is no mention of the additional bits that are added into the channel number that determine if the channel is used as a direct stepper controller with 1 and 2 prefixes. The 32 value is mentioned in the Fx1616BA User's manual for use with the StepMove statements.
Just add it to the list of stuff that is neither obvious nor consistent.
Best regards,
Gary D*ckinson