User guide

7: Host/ICP Interface
DC 900-1338I 137
Input:
A0.L = address of NODEC_TYPE structure
Output: none
Access: task or ISR
7.4.3 XIO Read/Write (s_xio)
Issue a read or write request. Depending on the value of the funct field of the host
request header (Figure7–4 on page128), the
s_xio function issues a read or write
request.
C Interface:
s_xio ( p_hdr )
SREQ_HDR_TYPE *p_hdr;
p_hdr
: pointer to host request header
Assembly Interface:
TRAP #4
Input: A0.L = address of SREQ_HDR_TYPE structure
Output: none
Access:
task or ISR
7.5 Diagnostics
OS/Impact defines a global system table (GST) that can be accessed at a fixed offset
from the load address and contains information used for system initialization and diag-
nostic purposes. A number of four-byte entries are defined by the operating system as
unused and are available for use by ICP-resident system and SPS tasks. (See the
OS/Impact Operating System Programmer’s Guide for a definition of the GST.)