Part Number: SN65HVD888
Dear TI, my question is concerning the SN65HVD888 and its ability to auto polarity correct.
Per the spec, for the SN65HVD888 to detect and do bus polarity correction, the following 3 condition must be met:
• A failsafe-biasing network (commonly at the master node) must define the signal polarity of the bus
• A slave node must enable the receiver and disable the driver (RE = DE = Low)
• The bus must idle for the failsafe time, tFS-max
Based on the above;
1. How is the above process affected by powering the device up?
2. Do those 3 conditions always allow the device to perform bus polarity correction, even if the device has already latched in a polarity correcting event.
3. Can the polarity correcting event be done over and over again as long as the device is powered on and the above 3 conditions are met?
4. Without a power up cycle, will the SN65HVD888 perform polarity correction when the above conditions met, even if the source of the failsafe-biasing network is hot-swapped on the fly?
What I want to achieve is the ability to allow a main computer with a SN65HVD888 to auto correct polarity whenever a new failsafe-biasing 485 driver is hot-swapped on to the network.
Is the above possible and if so, what issues could interfere with functionality?
Thx
Jeff Boyer | Director Of Engineering | TekMagic
M: +1-484-364-8351
Email: Jeff.B@TekMagic.net
