RE: Full-Duplex Serial Driver

schwiegjc

The ASCII data stream from a sensor can be successfully read using Serin_Wait(2,@DataIn,"T",4800,mode,8) function (mode=1 or non-inverted) but does not work with Full-Duplex Serial Driver start(2, 2, mode, 4800) function. Is it because of the value of the mode variable? Note. The mode variable never seems to be assigned in the Full-Duplex Serial Driver.

The mode variable is defined for Serin-Wait function as:
Mode: 0 = Inverted - Normally low Constant: BS2#Inv
1 = Non-Inverted - Normally High Constant: BS2#NI

The mode variable is defined for start function as:
'' mode bit 0 = invert rx
'' mode bit 1 = invert tx
'' mode bit 2 = open-drain/source tx
'' mode bit 3 = ignore tx echo on rx

Mike Green

The mode variable is used differently in the two objects (BS2 Compatibility Library and Full Duplex Serial Driver). For FullDuplexSerial, try mode=0. The Spin portion of the driver passes the start parameters as a block of 4 longs to the assembly portion of the driver. That's why there's no assignment.

schwiegjc

The ascii signal data is transmitted with its bits not inverted. Setting the mode variable to 1 for the SERIN_WAIT function instructs the function not to invert the bits. For the Full Duplex Serial Driver, there does not seem to be method to instruct the assembly code not to invert the bits.

Mike Green

Not true. The mode bits have both 0 (false) and 1 (true) values. If mode bit 0 is a 0, it means don't invert rx.

schwiegjc

Thank you. I suspected that previous statement was incorrect. I have tried the Full Duplex Serial Driver (set mode to 0) and it does not seem to work. The Serin_Wait function does work. I plan to further determine the problem.