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SPI RAM 23LC1024 (Microchip) 1Mbit see: http://mbed.org/users/okini3939/notebook/extend-memory/
Revision 0:c5ba7d914282, committed 2012-11-09
- Comitter:
- okini3939
- Date:
- Fri Nov 09 00:32:20 2012 +0000
- Child:
- 1:a7b1803dfa44
- Commit message:
- 1st build
Changed in this revision
| main.cpp | Show annotated file Show diff for this revision Revisions of this file |
| mbed.bld | Show annotated file Show diff for this revision Revisions of this file |
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/main.cpp Fri Nov 09 00:32:20 2012 +0000
@@ -0,0 +1,88 @@
+/*
+ * SPI RAM 23LC1024 (Microchip)
+ */
+#include "mbed.h"
+
+#define CMD_READ 0x03
+#define CMD_WRITE 0x02
+#define CMD_RDMR 0x05
+#define CMD_WRMR 0x01
+
+DigitalOut myled(LED1);
+Serial pc(USBTX, USBRX);
+
+SPI spi(p11, p12, p13); // mosi, miso, sclk
+DigitalOut cs(p17);
+
+int ram_write (int addr, char *buf, int len) {
+ int i;
+
+ cs = 0;
+ spi.write(CMD_WRITE);
+ spi.write((addr >> 16) & 0xff);
+ spi.write((addr >> 8) & 0xff);
+ spi.write(addr & 0xff);
+
+ for (i = 0; i < len; i ++) {
+ spi.write(buf[i]);
+ }
+ cs = 1;
+ return i;
+}
+
+int ram_read (int addr, char *buf, int len) {
+ int i;
+
+ cs = 0;
+ spi.write(CMD_READ);
+ spi.write((addr >> 16) & 0xff);
+ spi.write((addr >> 8) & 0xff);
+ spi.write(addr & 0xff);
+
+ for (i = 0; i < len; i ++) {
+ buf[i] = spi.write(0);
+ }
+ cs = 1;
+ return i;
+}
+
+int main() {
+ int i;
+ char buf[256];
+
+ cs = 1;
+ pc.baud(115200);
+ wait_ms(500);
+
+ cs = 0;
+ spi.write(CMD_RDMR);
+ printf("RAM mode: %02x\r\n", spi.write(0));
+ cs = 1;
+
+ printf("RAM write\r\n");
+ strcpy(buf, "Hello!");
+ ram_write(0, buf, 6);
+
+ for (i = 0; i < 256; i ++) {
+ buf[i] = i;
+ }
+ ram_write(6, buf, 256);
+
+ wait_ms(500);
+ memset(buf, 0, 256);
+
+ printf("RAM read\r\n");
+ ram_read(0, buf, 256);
+ for (i = 0; i < 256; i ++) {
+ printf(" %02x", buf[i]);
+ if ((i & 0x0f) == 0x0f)
+ printf("\r\n");
+ }
+
+ while(1) {
+ myled = 1;
+ wait(0.2);
+ myled = 0;
+ wait(0.2);
+ }
+}
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/mbed.bld Fri Nov 09 00:32:20 2012 +0000 @@ -0,0 +1,1 @@ +http://mbed.org/users/mbed_official/code/mbed/builds/e2ed12d17f06 \ No newline at end of file