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#include <stdio.h>
#include <stddef.h>
#include "wirish.h"
#include "fsmc.h"
#define LED BOARD_LED_PIN
// Start of FSMC SRAM bank 1
static uint16 *const ptr_start = (uint16*)0x60000000;
// End of Maple Native SRAM chip address space (512K 16-bit words)
static uint16 *const ptr_end = (uint16*)0x60080000;
// For snprintf
static char buf[100];
void setup() {
pinMode(LED, OUTPUT);
digitalWrite(LED, HIGH);
Serial1.begin(115200);
Serial1.println("Hello World!");
Serial1.print("Initializing RAM chip... ");
fsmc_native_sram_init();
Serial1.println("Done.");
}
void test_single_write() {
uint16 *ptr = ptr_start;
uint16 tmp;
Serial1.print("Writing 0x1234... ");
*ptr = 0x1234;
Serial1.println("Done.");
Serial1.print("Reading... ");
tmp = *ptr;
Serial1.print("Done: 0x");
Serial1.println(tmp, HEX);
if (tmp != 0x1234) {
Serial1.println("Mismatch, abort.");
ASSERT(0);
}
}
void test_all_addresses() {
uint32 start, end;
uint16 count = 0;
uint16 *ptr;
Serial1.println("Now writing all memory addresses (unrolled loop)");
SerialUSB.end();
start = micros();
for (ptr = ptr_start; ptr < ptr_end;) {
*ptr++ = count++;
*ptr++ = count++;
*ptr++ = count++;
*ptr++ = count++;
*ptr++ = count++;
*ptr++ = count++;
*ptr++ = count++;
*ptr++ = count++;
*ptr++ = count++;
*ptr++ = count++;
*ptr++ = count++;
*ptr++ = count++;
*ptr++ = count++;
*ptr++ = count++;
*ptr++ = count++;
*ptr++ = count++;
}
end = micros();
SerialUSB.begin();
Serial1.print("Done. Elapsed time (us): ");
Serial1.println(end - start);
Serial1.println("Validating writes.");
for (ptr = ptr_start, count = 0; ptr < ptr_end; ptr++, count++) {
if (*ptr != count) {
snprintf(buf, sizeof buf, "mismatch: %p = 0x%xu, should be 0x%xu.",
ptr, *ptr, count);
Serial1.println(buf);
ASSERT(0);
}
}
ptrdiff_t nwrites = ptr_end - ptr_start;
double us_per_write = double(end-start) / double(nwrites);
Serial1.println("Done; all writes seem valid.");
snprintf(buf, sizeof buf,
"Number of writes = %d; avg. time per write = %g us (%g MHz)",
nwrites, us_per_write, 1 / us_per_write);
Serial1.println(buf);
}
__attribute__((constructor)) void premain() {
init();
}
int main(void) {
setup();
test_single_write();
test_all_addresses();
Serial1.println("Tests pass, finished.");
while (true)
;
return 0;
}
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