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Update mbed_overrides.c 

Added calls to "crc16" routine, as well as the required #include and #define
pull/1216/head
chris-styles 2015-07-07 15:20:59 +01:00
parent 41ff2c8773
commit ee35963b3d
1 changed files with 24 additions and 26 deletions
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50
libraries/mbed/targets/hal/TARGET_Freescale/TARGET_KPSDK_MCUS/TARGET_MCU_K64F/TARGET_FRDM/mbed_overrides.c
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@ -15,6 +15,9 @@
*/
#include "gpio_api.h"
#define CRC16
#include "crc.h"
// called before main - implement here if board needs it ortherwise, let
// the application override this if necessary
//void mbed_sdk_init()
@ -35,40 +38,35 @@ void NMI_Handler(void)
void mbed_mac_address(char *mac)
{
// Making a random-as-possible MAC from 3 16 bit seeds and load of XOR'ing
uint16_t MAC[3]; // 3 16 bits words for the MAC
uint32_t UUID_LOC_BASE = 0x40048054;
// three random seeds to make a MAC
MAC[0] = 0x2055;
MAC[1] = 0x5c44;
MAC[2] = 0x79fe;
// XOR in each halfword of the UUID into each seed
for (int i=0;i<3;i++) {
for (int j=0;j<8;j++) {
MAC[i] ^= (*(uint32_t *)(UUID_LOC_BASE+(0x2*j)));
}
}
unsigned int UUID_LOC_BASE = 0x40048054; // First adddress of the 4-word UUID
char uuid[16]; // So we can take a local copy of the UUID
uint32_t MAC[3]; // 3 16 bits words for the MAC
// copy the UUID to the variable MAC[]
memcpy(uuid,(const void*)UUID_LOC_BASE,sizeof(uuid));
mac[0] = MAC[2] >> 8;
mac[1] = MAC[2];
// generate three CRC16's using different slices of the UUID
MAC[0] = crcSlow(uuid, 8); // most significant half-word
MAC[1] = crcSlow(uuid, 12);
MAC[2] = crcSlow(uuid, 16); // least significant half word
// The network stack expects an array of 6 bytes
// so we copy, and shift and copy from the half-word array to the byte array
mac[0] = MAC[0] >> 8;
mac[1] = MAC[0];
mac[2] = MAC[1] >> 8;
mac[3] = MAC[1];
mac[4] = MAC[0] >> 8;
mac[5] = MAC[0];
mac[4] = MAC[2] >> 8;
mac[5] = MAC[2];
// we only want bottom 16 bits of word1 (MAC bits 32-47)
// and bit 9 forced to 1, bit 8 forced to 0
// Locally administered MAC, reduced conflicts
// We want to force bits [1:0] of the most significant byte [0]
// to be "10"
// http://en.wikipedia.org/wiki/MAC_address
// uint32_t word1 = *(uint32_t *)UUID_LOC_WORD1;
mac[0] |= 0x02;
mac[0] &= 0xFE;
mac[0] |= 0x02; // force bit 1 to a "1" = "Locally Administered"
mac[0] &= 0xFE; // force bit 0 to a "0" = Unicast
}