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Finish SINGLESPEED option support

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This commit is contained in:
WestfW
2018-08-05 18:51:42 -07:00
parent ee87d274df
commit b30d32e152
2 changed files with 22 additions and 3 deletions
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8
optiboot/bootloaders/optiboot/baudcheck.c
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@@ -32,7 +32,11 @@ fcpu=${fcpu/U/}
/*
* Compute the divisor
*/
#ifdef SINGLESPEED
BAUD_SETTING=$(( ( ($fcpu + $bps * 8) / (($bps * 16))) - 1 ))
#else
BAUD_SETTING=$(( ( ($fcpu + $bps * 4) / (($bps * 8))) - 1 ))
#endif
// echo baud setting = $BAUD_SETTING
/*
@@ -40,7 +44,11 @@ BAUD_SETTING=$(( ( ($fcpu + $bps * 4) / (($bps * 8))) - 1 ))
* And the error. Since we're all integers, we have to calculate
* the tenths part of the error separately.
*/
#ifdef SINGLESPEED
BAUD_ACTUAL=$(( ($fcpu/(16 * (($BAUD_SETTING)+1))) ))
#else
BAUD_ACTUAL=$(( ($fcpu/(8 * (($BAUD_SETTING)+1))) ))
#endif
BAUD_ERROR=$(( (( 100*($BAUD_ACTUAL - $bps) ) / $bps) ))
ERR_TS=$(( ((( 1000*($BAUD_ACTUAL - $bps) ) / $bps) - $BAUD_ERROR * 10) ))
ERR_TENTHS=$(( ERR_TS > 0 ? ERR_TS: -ERR_TS ))

17
optiboot/bootloaders/optiboot/optiboot.c
View File

@@ -326,8 +326,15 @@ typedef union {
#define UART 0
#endif
#ifdef SINGLESPEED
/* Single speed option */
#define BAUD_SETTING (( (F_CPU + BAUD_RATE * 8L) / ((BAUD_RATE * 16L))) - 1 )
#define BAUD_ACTUAL (F_CPU/(16 * ((BAUD_SETTING)+1)))
#else
/* Normal U2X usage */
#define BAUD_SETTING (( (F_CPU + BAUD_RATE * 4L) / ((BAUD_RATE * 8L))) - 1 )
#define BAUD_ACTUAL (F_CPU/(8 * ((BAUD_SETTING)+1)))
#endif
#if BAUD_ACTUAL <= BAUD_RATE
#define BAUD_ERROR (( 100*(BAUD_RATE - BAUD_ACTUAL) ) / BAUD_RATE)
#if BAUD_ERROR >= 5
@@ -344,14 +351,14 @@ typedef union {
#endif
#endif
#if (F_CPU + BAUD_RATE * 4L) / (BAUD_RATE * 8L) - 1 > 250
#if BAUD_SETTING > 250
#error Unachievable baud rate (too slow) BAUD_RATE
#endif // baud rate slow check
#if (F_CPU + BAUD_RATE * 4L) / (BAUD_RATE * 8L) - 1 < 3
#if (BAUD_SETTING - 1) < 3
#if BAUD_ERROR != 0 // permit high bitrates (ie 1Mbps@16MHz) if error is zero
#error Unachievable baud rate (too fast) BAUD_RATE
#endif
#endif // baud rate fastn check
#endif // baud rate fast check
/* Watchdog settings */
#define WATCHDOG_OFF (0)
@@ -559,12 +566,16 @@ int main(void) {
#ifndef SOFT_UART
#if defined(__AVR_ATmega8__) || defined (__AVR_ATmega32__) || defined (__AVR_ATmega16__)
#ifndef SINGLESPEED
UCSRA = _BV(U2X); //Double speed mode USART
#endif
UCSRB = _BV(RXEN) | _BV(TXEN); // enable Rx & Tx
UCSRC = _BV(URSEL) | _BV(UCSZ1) | _BV(UCSZ0); // config USART; 8N1
UBRRL = (uint8_t)( (F_CPU + BAUD_RATE * 4L) / (BAUD_RATE * 8L) - 1 );
#else
#ifndef SINGLESPEED
UART_SRA = _BV(U2X0); //Double speed mode USART0
#endif
UART_SRB = _BV(RXEN0) | _BV(TXEN0);
UART_SRC = _BV(UCSZ00) | _BV(UCSZ01);
UART_SRL = (uint8_t)( (F_CPU + BAUD_RATE * 4L) / (BAUD_RATE * 8L) - 1 );