Hello:
Please, beaware that RMII (MII is not supported by LPC17xx) needs a 50MHz clock,
not 25MHz like in MII.
Unless you had a typo, this should be the problem.
Regards;
GS
--- In l..., Prakash Rajoli wrote:
>
> Hello,
>
> During configuration of Ethernet, JTAG losing communication with the target.
>
> In LPC17xx manual there is a remark as follow
>
> Remark: when initializing the Ethernet block, it is important to first
configure the PHY and
> insure that reference clocks (ENET_REF_CLK signal in RMII mode, or both
> ENET_RX_CLK and ENET_TX_CLK signals in MII mode) are present at the external
pins
> and connected to the EMAC module (selecting the appropriate pins using the
PINSEL
> registers) prior to continuing with Ethernet configuration. Otherwise the CPU
can become
> locked and no further functionality will be possible. This will cause JTAG
lose
> communication with the target, if debug mode is being used.
>
> Initialization have following code,
>
>
>
> /* Power Up the EMAC controller. */
>
> SC->PCONP |= 0x40000000;
>
>
>
> /* Enable P1 Ethernet Pins. */
>
> PINCON->PINSEL2 = 0x50150105;
>
> PINCON->PINSEL3 = (PINCON->PINSEL3 & ~0x0000000F) |
> 0x00000005;
>
>
>
> /* Reset all EMAC internal modules. */
>
> EMAC->MAC1 = MAC1_RES_TX | MAC1_RES_MCS_TX | MAC1_RES_RX |
> MAC1_RES_MCS_RX |
>
> MAC1_SIM_RES | MAC1_SOFT_RES;
>
> EMAC->Command = CR_REG_RES | CR_TX_RES | CR_RX_RES;
>
>
>
> Is there any problem in this configuration?
>
> KS8721 PHY is the device which I am using in my board and 25 MHz oscillator be
connected to the device X1 pin. Is there oscillator problem?
>
> -Prakash
>
> 9886545216
>
