© National Instruments Corporation 5-1 GPIB-1014 User Manual
Chapter 5Programming Considerations
This chapter explains the initialization process, sending/receiving messages, and the
serial/parallel poll process. Additional information on programming the µPD7210 GPIB
interface chip can be obtained from the
µ
PD7210 GPIB-IFC User Manual by NEC Electronics
U.S.A., Inc. More specific information on programming the 68450 DMAC chip can be obtained
from Hitachi and Motorola technical data.

Initialization

On power-up, the VMEbus system typically issues a system reset (SYSRESET*) that drives the
GPIB-1014 RESET* signal active. This action clears both Configuration Registers and
initializes the following circuitry:
Timing State Machine
DMA Gating and Control
GPIB Synchronization and Interrupt Control
• Interrupter
DTB Requester
µPD7210 TLC
68450 DMAC
The GPIB-1014 also has another method for initializing the circuitry on the card. If the Local
Master Reset (LMR) bit in Configuration Register 2 is set, the RESET signal is driven and the
GPIB-1014 is initialized in the same manner.
The NEC µPD7210 Talker/Listener/Controller (TLC) integrated circuit is initialized as follows:
The local message pon is set and the interface functions are placed in their idle states (SIDS,
AIDS, TIDS, SPIS, TPIS, LIDS, LPIS, NPRS, LOCS, PPIS, PUCS, CIDS, SRIS, SIIS).
All bits of the Serial Poll Mode Register (SPMR) are cleared.
The End Or Identify (EOI) bit is cleared.
All bits of the Auxiliary Registers A, B, and E (AUXRA, AUXRB, and AUXRE) are cleared.
The Parallel Poll Flag and Request System Control (RSC) local message are cleared.
The Internal Clock Register (ICR) is set to a count of eight.