NAT9914 Operation

[RickD]

My group and I are in the process of programming a PIC microcontroller for use with the NAT 9914, our question is does the NAT 9914 when connected with the 160/162 parse the incomming IEEE 488.2 commands and queries for the address in the Address register or do we need to include the address in our software parsing routine?

Also, all IEEE 488.2 commands and queries start with the *, does this character appear in the BO register, or does the NAT9914 not send this to the microcontroller?

Thank You

[GPIB_Guru]

Good question. The NAT9914 (and all other GPIB ASICs that I am aware of) do not interpret any data bytes. The goal of the NAT9914 is to interpret command bytes and handle the communication protocol of IEEE 488.1.

When the NAT9914 detects command bytes that address it to be a listener, it will start handshaking data bytes on the GPIB. Each data byte received will cause the BO bit to set and the data byte to appear in the DIR register.

These data bytes must be passed to the application. The application will do the parsing for the standard commands and queries.

[Collin M]

The BI bit is set when a data byte is received, not the BO bit.

[GPIB_Guru]

:).