Import old unfinished FT232R bit-banging code for sim sniffing

This code never really worked due to large sample clock jitter, lost
USB messages and the lack of CLK sniffing ability

1 files changed, 120 insertions, 0 deletions

diff --git a/ft232r/bitbang.c b/ft232r/bitbang.c
new file mode 100644
index 0000000..e6b7916
--- /dev/null
+++ b/ft232r/bitbang.c
@@ -0,0 +1,120 @@
+/* This program is distributed under the GPL, version 2 */
+
+#include <stdio.h>
+#include <unistd.h>
+#include <string.h>
+#include <ftdi.h>
+
+#include "soft_uart.h"
+
+static unsigned char last;
+static struct suart_data su;
+
+#define CLK_BIT	0x20
+#define RST_BIT	0x08
+#define IO_BIT	0x02
+
+static void handle_sample(unsigned char c)
+{
+	uint8_t rst = 0, io = 0, clk = 0;
+
+	if (c & RST_BIT)
+		rst = 1;
+
+	if (c & CLK_BIT)
+		clk = 1;
+
+	if (c & IO_BIT)
+		io = 1;
+
+#if 0
+	if ((c & 0xf) != last) {
+		printf("%02x ", c & ~(CLK_BIT|IO_BIT)); 
+	}
+	last = c;
+#endif
+#if 0
+	if (c & RST_BIT)
+		printf("-");
+	else
+		printf("_");
+#endif
+#if 1
+	if (c & IO_BIT)
+		printf("-");
+	else
+		printf("_");
+#endif
+	//suart_process_sample_bit(&su, clk, rst, io);
+}
+
+#define OVERSAMPLING 4
+
+int main(int argc, char **argv)
+{
+    struct ftdi_context ftdic;
+    int f,i;
+    unsigned char buf[1<<16];
+	//unsigned int sample_rate = 12900 * OVERSAMPLING; /* 192kS/s */
+	unsigned int sample_rate = (1 << 18);
+
+	memset(&su, 0, sizeof(su));
+
+    if (ftdi_init(&ftdic) < 0)
+    {
+        fprintf(stderr, "ftdi_init failed\n");
+        return EXIT_FAILURE;
+    }
+
+    f = ftdi_usb_open(&ftdic, 0x0403, 0x6001);
+
+    if (f < 0 && f != -5)
+    {
+        fprintf(stderr, "unable to open ftdi device: %d (%s)\n", f, ftdi_get_error_string(&ftdic));
+        exit(-1);
+    }
+
+    printf("ftdi open succeeded: %d\n",f);
+
+    printf("enabling bitbang mode\n");
+    //ftdi_disable_bitbang(&ftdic);
+    //ftdi_set_line_property(&ftdic, 8, 1, EVEN);
+    ftdi_set_bitmode(&ftdic, 0x0, BITMODE_BITBANG);
+    ftdi_read_data_set_chunksize(&ftdic, sizeof(buf));
+    ftdi_set_latency_timer(&ftdic, 255);
+    //ftdi_set_latency_timer(&ftdic, 1);
+    //f = ftdi_set_baudrate(&ftdic, 300000);
+    f = ftdi_set_baudrate(&ftdic, sample_rate/16);
+    if (f < 0) {
+	fprintf(stderr, "error setting baudrate\n");
+	exit(1);
+    }
+
+	su.samplerate = sample_rate;
+	su.recip_etu = sample_rate / OVERSAMPLING;
+	su.num_bits = 8;
+	suart_init(&su);
+
+    while (1) {
+	memset(buf, 0, sizeof(buf));
+	f = ftdi_read_data(&ftdic, buf, sizeof(buf));
+        if (f < 0) {
+		fprintf(stderr,"read failed for 0x%x, error %d (%s)\n",buf[0],f, ftdi_get_error_string(&ftdic));
+		exit(1);
+        }
+	//printf("ftdi returned %u (of %u)\n", f, sizeof(buf));
+	for (i = 0; i < f; i++) {
+		handle_sample(buf[i]);
+	}
+	fflush(stdout);
+	//num_samples += f;
+    }
+
+    printf("\n");
+
+    printf("disabling bitbang mode\n");
+    ftdi_disable_bitbang(&ftdic);
+
+    ftdi_usb_close(&ftdic);
+    ftdi_deinit(&ftdic);
+}