AN2836 Freescale Semiconductor / Motorola, AN2836 Datasheet - Page 25

• Manufacturer Part Number: AN2836
• Description: Web Server Development with MC9S12NE64 and OpenTCP
• Manufacturer: Freescale Semiconductor / Motorola

//============================================================
//Buffer Configuration
//============================================================
#define BUFMAP 4
.
.
.
//============================================================
//EMAC FILTERING CONTROL
//============================================================
//Address Filtering; RXMODE setting: PAUSE frame supported, Accept Unique, Brodcast, MultiCast
#define
#define
#define
//Ethertype Control
#define ETYPE_PET
#define ETYPE_EMW
#define ETYPE_IPV6
#define ETYPE_ARP
#define ETYPE_IPV4
#define ETYPE_IEEE
#define ETYPE_ALL
//Programmable Ethertype
#define ETYPE_PRG
//Receive maximum frame length
#define RX_MAX_FL
#define DELETE_BFRAMES
.
.
.
P&E_ICD_linker.prm
An excerpt of the source code for P&E_ICD_linker.prm is provided below. P&E_ICD_linker.prm must be
modified so that it is compatible with ne64config.h ’s BUFMAP configuration settings. BUFMAP configures
the Ethernet buffer space which consist of three buffer (one transmit buffer and two receive buffers) that
are each designed to only hold one Ethernet frame at any given time. The BUFMAP field is a component
of the BUFCFG register.
The RAM section shows the remainder available system RAM for the user application. This RAM for the
user application is the difference between the total system RAM (8K) and the amount of system RAM
allocated for the Ethernet buffer.
Table 7
Because the maximum size of an Ethernet frame is approximately 1.5K, a setting of BUFMAP = 4 would
allow each of the MC9S12NE64’s three buffers to hold one frame of the maximum allowable size.
Freescale Semiconductor
itemizes the remainder of RAM available for the user application based on the value of BUFMAP.
CON_MULTIC
PROM_MODE
BRODC_REJ
0
0
0
0
0
0
0
1
Web Server Development with MC9S12NE64 and OpenTCP, Rev. 0
/**< Enter Value if ETYPE_PET is set for filter target */
1536
0
0
0
0
/**< set to 1 to delete packets larger than RX_MAX_FL */
/**< Receive maximum frame length */
Overview of a Web Server Developed Using OpenTCP TCP/IP Stack
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