scopes: Adapt/fix some code comments, cosmetics.

[sigrok-firmware-fx2lafw.git] / hantek_6022be.c

diff --git a/hantek_6022be.c b/hantek_6022be.c
index d3d85e27b829a8ccd3db5eec245e49314c0ec982..232237eb1296b2147222d5c9db271450f4ce460d 100644 (file)
--- a/hantek_6022be.c
+++ b/hantek_6022be.c
@@ -15,8 +15,7 @@
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+ * License along with this library; if not, see <http://www.gnu.org/licenses/>.
  */
 
 #include <fx2macros.h>
@@ -67,7 +66,9 @@ void suspend_isr(void) __interrupt SUSPEND_ISR
 
 void timer2_isr(void) __interrupt TF2_ISR
 {
+       /* Toggle the 1kHz calibration pin, only accurate up to ca. 8MHz. */
        PA7 = !PA7;
+
        if (ledcounter) {
                if (--ledcounter == 0) {
                        /* Clear LED. */
@@ -75,6 +76,7 @@ void timer2_isr(void) __interrupt TF2_ISR
                        PC1 = 1;
                }
        }
+
        TF2 = 0;
 }
 
@@ -243,23 +245,26 @@ static BOOL set_samplerate(BYTE rate)
        IFCONFIG = samplerates[i].ifcfg;
 
        AUTOPTRSETUP = 7;
-       AUTOPTRH2 = 0xE4;
+       AUTOPTRH2 = 0xE4; /* 0xE400: GPIF waveform descriptor 0. */
        AUTOPTRL2 = 0x00;
 
        /*
         * The program for low-speed, e.g. 1 MHz, is:
-        * wait 24, CTL2=0, FIFO
-        * wait 23, CTL2=1
-        * jump 0, CTL2=1
+        * wait 24, CTLx=0, FIFO
+        * wait 23, CTLx=1
+        * jump 0, CTLx=1
         *
         * The program for 24 MHz is:
-        * wait 1, CTL2=0, FIFO
-        * jump 0, CTL2=1
+        * wait 1, CTLx=0, FIFO
+        * jump 0, CTLx=1
         *
         * The program for 30/48 MHz is:
-        * jump 0, CTL2=Z, FIFO, LOOP
+        * jump 0, CTLx=Z, FIFO, LOOP
+        *
+        * (CTLx is device-dependent, could be e.g. CTL0 or CTL2.)
         */
 
+       /* LENGTH / BRANCH 0-7 */
        EXTAUTODAT2 = samplerates[i].wait0;
        EXTAUTODAT2 = samplerates[i].wait1;
        EXTAUTODAT2 = 1;
@@ -269,24 +274,27 @@ static BOOL set_samplerate(BYTE rate)
        EXTAUTODAT2 = 0;
        EXTAUTODAT2 = 0;
 
+       /* OPCODE 0-7 */
        EXTAUTODAT2 = samplerates[i].opc0;
        EXTAUTODAT2 = samplerates[i].opc1;
-       EXTAUTODAT2 = 1;
+       EXTAUTODAT2 = 1; /* DATA=0 DP=1 */
        EXTAUTODAT2 = 0;
        EXTAUTODAT2 = 0;
        EXTAUTODAT2 = 0;
        EXTAUTODAT2 = 0;
        EXTAUTODAT2 = 0;
 
+       /* OUTPUT 0-7 */
        EXTAUTODAT2 = samplerates[i].out0;
-       EXTAUTODAT2 = 0x44;
-       EXTAUTODAT2 = 0x44;
-       EXTAUTODAT2 = 0x00;
-       EXTAUTODAT2 = 0x00;
-       EXTAUTODAT2 = 0x00;
-       EXTAUTODAT2 = 0x00;
-       EXTAUTODAT2 = 0x00;
+       EXTAUTODAT2 = 0x44; /* OE2=1, CTL2=1 */
+       EXTAUTODAT2 = 0x44; /* OE2=1, CTL2=1 */
+       EXTAUTODAT2 = 0;
+       EXTAUTODAT2 = 0;
+       EXTAUTODAT2 = 0;
+       EXTAUTODAT2 = 0;
+       EXTAUTODAT2 = 0;
 
+       /* LOGIC FUNCTION 0-7 */
        EXTAUTODAT2 = 0;
        EXTAUTODAT2 = 0;
        EXTAUTODAT2 = 0;
@@ -349,31 +357,26 @@ BOOL handle_vendorcommand(BYTE cmd)
        PC1 = 1;
        ledcounter = 1000;
 
-       switch (cmd) {
-       case 0xe0:
-       case 0xe1:
+       /* Clear EP0BCH/L for each valid command. */
+       if (cmd >= 0xe0 && cmd <= 0xe4) {
                EP0BCH = 0;
                EP0BCL = 0;
                while (EP0CS & bmEPBUSY);
+       }
+
+       switch (cmd) {
+       case 0xe0:
+       case 0xe1:
                set_voltage(cmd - 0xe0, EP0BUF[0]);
                return TRUE;
        case 0xe2:
-               EP0BCH = 0;
-               EP0BCL = 0;
-               while (EP0CS & bmEPBUSY);
                set_samplerate(EP0BUF[0]);
                return TRUE;
        case 0xe3:
-               EP0BCH = 0;
-               EP0BCL = 0;
-               while (EP0CS & bmEPBUSY);
                if (EP0BUF[0] == 1)
                        start_sampling();
                return TRUE;
        case 0xe4:
-               EP0BCH = 0;
-               EP0BCL = 0;
-               while (EP0CS & bmEPBUSY);
                set_numchannels(EP0BUF[0]);
                return TRUE;
        }
@@ -387,8 +390,8 @@ static void init(void)
        EP8CFG = 0;
 
        /* In idle mode tristate all outputs. */
-       GPIFIDLECTL = 0x00;
-       GPIFCTLCFG = 0x80;
+       GPIFIDLECTL = 0x00; /* Don't enable CTL0-5 outputs. */
+       GPIFCTLCFG = 0x80; /* TRICTL=1. CTL0-2: CMOS outputs, tri-statable. */
        GPIFWFSELECT = 0x00;
        GPIFREADYSTAT = 0x00;
 
@@ -422,7 +425,7 @@ static void main(void)
 
        /* Init timer2. */
        RCAP2L = -500 & 0xff;
-       RCAP2H = (-500 >> 8) & 0xff;
+       RCAP2H = (-500 & 0xff00) >> 8;
        T2CON = 0;
        ET2 = 1;
        TR2 = 1;
@@ -444,7 +447,7 @@ static void main(void)
                        dosuspend = FALSE;
                        do {
                                /* Make sure ext wakeups are cleared. */
-                               WAKEUPCS |= bmWU|bmWU2;
+                               WAKEUPCS |= bmWU | bmWU2;
                                SUSPEND = 1;
                                PCON |= 1;
                                __asm