This test code in SysTickHanlder() should give you a rather
accurate clock with only a few seconds deviation per hour:
#include "serial.h"
#include "sersendf.h"
void SysTick_Handler(void) {
static uint32_t count = 0;
static uint8_t minutes = 0, seconds = 0;
count++;
if ( ! (count % 500)) { // A full second.
seconds++;
if ( ! (seconds % 60)) {
seconds = 0;
minutes++;
}
sersendf_P(PSTR("%su:"), minutes);
if (seconds < 10)
serial_writechar('0');
sersendf_P(PSTR("%su\n"), seconds);
}
[...]
This enables pinio_init(), power_on() and power_off(). Now one
can turn on the power supply with M119 and turn it off with M2.
Code changes were neccessary. Setting a pin first, then making
it an output doesn't work on ARM. A pin has to be an output
before it permanently accepts a given state. As I was never
sure the former strategy actually worked on AVR, the order of
these two steps was changed for both, AVR and ARM.
Again, the whole file compiled flawlessly without change. Still,
to get it linked as well, most of the functionality had to
be #ifdef'd out.
Nevertheless, the firmware shows first signs of life, e.g. M115
works.
Just did it, no code changes neccessary. Except ajusting the
boundaries to not yet ported code.
Successful tests: controller answers with "ok", just like an AVR.
Binary size raised, of course:
SIZES ARM... lpc1114
FLASH : 3064 bytes 10%
RAM : 194 bytes 5%
EEPROM : 0 bytes 0%
Accuracy is pretty good, see committed comments :-)
Code used for testing, in main():
uint32_t i;
SET_OUTPUT(PIO0_1);
while (1) {
// 10 seconds for each frequency, so we
// can measure all three with one upload.
for (i = 10000; i > 0; i--) {
WRITE(PIO0_1, 1);
delay_us(1000);
WRITE(PIO0_1, 0);
delay_us(1000);
}
for (i = 1000; i > 0; i--) {
WRITE(PIO0_1, 1);
delay_us(10000);
WRITE(PIO0_1, 0);
delay_us(10000);
}
for (i = 200; i > 0; i--) {
WRITE(PIO0_1, 1);
delay_us(65000);
WRITE(PIO0_1, 0);
delay_us(65000);
}
}
We have only one UART, we use only one UART, so it's pointless to
do pin mapping calculations at runtime.
Binary size down by 268 bytes:
SIZES ARM... lpc1114
FLASH : 1724 bytes 6%
RAM : 156 bytes 4%
EEPROM : 0 bytes 0%
Pretty complex, this MBED system, it requires no less than
24 additional files. This will be fleshd out before too long.
SIZES ARM... lpc1114
FLASH : 5956 bytes 19%
RAM : 176 bytes 5%
EEPROM : 0 bytes 0%
Markus Hitter