Commit 33a46b24 authored by Dean Camera's avatar Dean Camera
Browse files

PDI NVM enable is fast enough that bare polling is enough without a fixed...

PDI NVM enable is fast enough that bare polling is enough without a fixed delay in between each attempt. Make sure the USART transmitter is enabled explicitly when the USART is configured, so that repeated attempts to re-enter PDI mode don't fail due to TXEN not being set.
parent 66201a05
...@@ -115,11 +115,9 @@ static void PDIProtocol_EnterXPROGMode(void) ...@@ -115,11 +115,9 @@ static void PDIProtocol_EnterXPROGMode(void)
PDITarget_SendByte(PDI_NVMENABLE_KEY[i - 1]); PDITarget_SendByte(PDI_NVMENABLE_KEY[i - 1]);
/* Poll the STATUS register to check to see if NVM access has been enabled */ /* Poll the STATUS register to check to see if NVM access has been enabled */
uint8_t NVMAttemptsRemaining = 150; uint8_t NVMAttemptsRemaining = 255;
while (NVMAttemptsRemaining) while (NVMAttemptsRemaining)
{ {
_delay_ms(1);
PDITarget_SendByte(PDI_CMD_LDCS | PD_STATUS_REG); PDITarget_SendByte(PDI_CMD_LDCS | PD_STATUS_REG);
if (PDITarget_ReceiveByte() & PDI_STATUS_NVM) if (PDITarget_ReceiveByte() & PDI_STATUS_NVM)
break; break;
......
...@@ -173,6 +173,7 @@ void PDITarget_EnableTargetPDI(void) ...@@ -173,6 +173,7 @@ void PDITarget_EnableTargetPDI(void)
/* Set up the synchronous USART for XMEGA communications - /* Set up the synchronous USART for XMEGA communications -
8 data bits, even parity, 2 stop bits */ 8 data bits, even parity, 2 stop bits */
UBRR1 = 10; UBRR1 = 10;
UCSR1B = (1 << TXEN1);
UCSR1C = (1 << UMSEL10) | (1 << UPM11) | (1 << USBS1) | (1 << UCSZ11) | (1 << UCSZ10) | (1 << UCPOL1); UCSR1C = (1 << UMSEL10) | (1 << UPM11) | (1 << USBS1) | (1 << UCSZ11) | (1 << UCSZ10) | (1 << UCPOL1);
/* Send two BREAKs of 12 bits each to enable PDI interface (need at least 16 idle bits) */ /* Send two BREAKs of 12 bits each to enable PDI interface (need at least 16 idle bits) */
...@@ -182,9 +183,10 @@ void PDITarget_EnableTargetPDI(void) ...@@ -182,9 +183,10 @@ void PDITarget_EnableTargetPDI(void)
void PDITarget_DisableTargetPDI(void) void PDITarget_DisableTargetPDI(void)
{ {
/* Turn of receiver and transmitter of the USART, clear settings */ /* Turn off receiver and transmitter of the USART, clear settings */
UCSR1B = 0; UCSR1A |= (1 << TXC1) | (1 << RXC1);
UCSR1C = 0; UCSR1B = 0;
UCSR1C = 0;
/* Set all USART lines as input, tristate */ /* Set all USART lines as input, tristate */
DDRD &= ~((1 << 5) | (1 << 3)); DDRD &= ~((1 << 5) | (1 << 3));
......
Supports Markdown
0% or .
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment