Users Guide: Network Microcontroller Supplement User Manual

High-Speed Microcontroller User’s
Guide: Network Microcontroller
Supplement
203
DHCP FUNCTIONS
dhcp_init
Description: int dhcp_init(void);
The dhcp_init function initializes the DHCP client. dhcp_init starts a DHCP client task and returns to the caller. This function
returns 0 in the accumulator if successful, nonzero otherwise. To read the address DHCP has configured (only valid if DHCP
is in bound, renewing or rebinding state—see dhcp_status), use the socket layer function getnetworkparams.
DHCP is implemented for IPv4 only. The IPv6 por
tion of the network stack uses neighbor discovery.
The DHCP client calls DHCPnotify from the function redirect table when it acquires or loses an IP. The default DHCPnotify rou-
tine supplied in the function redirect table (when ROM_redirect_init is executed by the DS80C400 silicon software) is
rom_dhcp_notify.
dhcp_setup
Description: The dhcp_setup function is used by dhcp_init and dhcp_stop.
dhcp_startup
Description: The dhcp_startup function is used by dhcp_init.
dhcp_run
Description: The dhcp_run function is used by dhcp_init.
dhcp_status
Description: int dhcp_status(void);
The dhcp_status function r
eturns the DHCP state. The possible DHCP state return values are listed as follows. See the
RFC2131 for a description of these DHCP states.
DHCP ST
ATE RETURN VALUE
INIT 0
SELECTING 1
REQUESTING 2
INITREBOOT 3
REBOOTING 4
BOUND 5
RENEWING 6
REBINDING 7
INPUT DESCRIPTION OUTPUT DESCRIPTION
— ACC Return value
Example: ROMCALL dhcp_status
INPUT PARAMETER#–DESCRIPTION OUTPUT DESCRIPTION
— ACC
R0
Return value (= 0 for success)
Return value (bit-wise OR of flags)
Example: ROMCALL dhcp_init
Maxim Integrated