UART 1 issue

Discussion created by lpcware Employee on Jun 15, 2016
Latest reply on Jun 15, 2016 by lpcware
Content originally posted in LPCWare by hetech on Sun Oct 12 22:22:32 MST 2014
I have some small code I wrote that uses USART 0 via IRQs.
It works fine with USART 0 or USART 2 (with minor changes), but if I try UART1, I cannot receive or send anything.
Of course I am changing the SCU pin assignments to suit the relevant UART for each test

Even without IRQs, Trying to send a byte via UART1 does nothing (I have checked the pin with a CRO).
UART1 is using PIN 63 / 65

LPC_SCU->SFSP5_6 = 4|(1<<6);// P5.6 GPIO2[15] UART1 TxD
LPC_SCU->SFSP5_7 = 4|(1<<6);// P5.7 GPIO2[7] UART1 RxD

LPC_CGU->BASE_UART1_CLK = (6<<24);// Set to XTAL (12MHz)

LPC_UART1->LCR= 3|(1<<7);// Line control
LPC_UART1->FDR= 5 | (8<<4);// Baud Divider*8/5
//LPC_UART1->DLL= 4;// Baud Diviser LSB 115,200
LPC_UART1->DLL= 8;// Baud Diviser LSB 57,600
LPC_UART1->DLM= 0x00000000;// Baud Diviser MSB
LPC_UART1->FCR= 0x00000007;// FIFO control
LPC_UART1->TER= 0x00000001;// TX EN
LPC_UART1->LCR= 3;// Line control
LPC_UART1->THR= 0x41;// TX 'A'
//LPC_UART1->IER= 2;// TX IRQ enabled