PAM Programming Manual

Link-Level Interfaces
PAM Programming Manual—142482
3-13
Formatting an SDU Header (Ethernet)
LLC1 SDU Header Format
The LLC1 SDU header formatted by this L2S primitive is defined as follows:
The fields of the LLC1 SDU header are defined as follows:
zSDU-Size
The number of bytes of buffer space required for this SDU, which is the number of
bytes for the header and data.
zForeign-SAP
The destination service access point address, as follows:
zLSAP
The link-level service access point address.
zMAC-Addr
Physical layer group media access control (MAC) address. The value specified
can be up to 12 hexadecimal digits (6 bytes).
zCtl
The Link-Level Control (LLC) control field for U-format PDUs.
zP-F-Flag
Optional input that allows applications to set or reset the poll (P) bit in command
PDUs to solicit a response from the addressed peer or the final (F) bit in response
PDUs to indicate a response to a solicitation (poll). The default value is false.
zRsp-Flag
An optional input that designates whether this PDU is a command (false) or a
response (true). The default value is false (command).
def ZL2S-DDL-LLC-SDU-Hdr.
02 zSDU-Size type ZSPI-DDL-INT.
02 zForeign-SAP type ZL2S-DDL-LLC-ADDR.
02 zCtl type ZSPI-DDL-BYTE.
02 zP-F-Flag type ZSPI-DDL-BYTE.
02 zRsp-Flag type ZSPI-DDL-BYTE.
02 zPri type ZSPI-DDL-BYTE.
02 zFiller type ZSPI-DDL-BYTE.
occurs 19 times.
end.
def ZL2S-DDL-LLC-Addr
02 zLSAP type ZSPI-DDL-INT.
O2 zMAC-Addr type ZSPI-DDL-BYTE.
occurs 6 times.
end.