Refactor and bugfix the delay adding code for analog capture

[sigrok-firmware-fx2lafw.git] / gpif-acquisition.c

diff --git a/gpif-acquisition.c b/gpif-acquisition.c
index 17a87b9e968a0bd91324f4073da0fed95e44ddf2..dbf740366f1a31d7003984ba2adaae653eb2983a 100644 (file)
--- a/gpif-acquisition.c
+++ b/gpif-acquisition.c
@@ -132,7 +132,7 @@ void gpif_init_la(void)
        gpif_acquiring = FALSE;
 }
 
-static void gpif_make_delay_state(volatile BYTE *pSTATE, uint8_t delay, uint8_t opcode, uint8_t output)
+static void gpif_make_delay_state(volatile BYTE *pSTATE, uint8_t delay, uint8_t output)
 {
        /*
         * DELAY
@@ -143,13 +143,12 @@ static void gpif_make_delay_state(volatile BYTE *pSTATE, uint8_t delay, uint8_t
        /*
         * OPCODE
         * SGL=0, GIN=0, INCAD=0, NEXT=0, DATA=0, DP=0
-        * Collect data in this state.
         */
-       pSTATE[8] = opcode;
+       pSTATE[8] = 0;
 
        /*
         * OUTPUT
-        * OE[0:3]=0, CTL[0:3]=0
+        * CTL[0:5]=output
         */
        pSTATE[16] = output;
 
@@ -160,7 +159,7 @@ static void gpif_make_delay_state(volatile BYTE *pSTATE, uint8_t delay, uint8_t
        pSTATE[24] = 0x00;
 }
 
-static void gpid_make_data_dp_state(volatile BYTE *pSTATE)
+static void gpif_make_data_dp_state(volatile BYTE *pSTATE)
 {
        /*
         * BRANCH
@@ -176,7 +175,7 @@ static void gpid_make_data_dp_state(volatile BYTE *pSTATE)
 
        /*
         * OUTPUT
-        * OE[0:3]=0, CTL[0:3]=0
+        * CTL[0:5]=0
         */
        pSTATE[16] = 0x00;
 
@@ -213,35 +212,38 @@ bool gpif_acquisition_start(const struct cmd_start_acquisition *cmd)
                           bmGSTATE | bmIFGPIF;
        }
 
-       if (cmd->flags & CMD_START_FLAGS_CLK_CTL2) {
-               uint8_t delay_1, delay_2;
-
-               /* We need a pulse where the CTL2 pin alternates states. */
-
-               /* Make the low pulse shorter then the high pulse. */
-               delay_2 = cmd->sample_delay_l >> 2;
-               /* Work around >12MHz case resulting in a 0 delay low pulse. */
-               if (delay_2 == 0)
-                       delay_2 = 1;
-               delay_1 = cmd->sample_delay_l - delay_2;
+       /* Populate delay states */
+       if ((cmd->sample_delay_h == 0 && cmd->sample_delay_l == 0) ||
+           cmd->sample_delay_h >= 6)
+               return false;
 
-               gpif_make_delay_state(pSTATE++, delay_2, 0x00, 0x40);
-               gpif_make_delay_state(pSTATE++, delay_1, 0x00, 0x46);
+       if (cmd->flags & CMD_START_FLAGS_CLK_CTL2) {
+               uint8_t delay_1, delay_2 = cmd->sample_delay_l;
+
+               /* We need a pulse where the CTL1 and CTL2 pins
+                * alternate states */
+               if (cmd->sample_delay_h) {
+                       for (i = 0; i < cmd->sample_delay_h; i++)
+                               gpif_make_delay_state(pSTATE++, 0, 0x06);
+               } else {
+                       delay_1 = delay_2 / 2;
+                       delay_2 -= delay_1;
+                       gpif_make_delay_state(pSTATE++, delay_1, 0x06);
+               }
+
+               /* cmd->sample_delay_l is always non-zero for the
+                * supported rates */
+               gpif_make_delay_state(pSTATE++, delay_2, 0x00);
        } else {
-               /* Populate delay states. */
-               if ((cmd->sample_delay_h == 0 && cmd->sample_delay_l == 0) ||
-                       cmd->sample_delay_h >= 6)
-                       return false;
-
                for (i = 0; i < cmd->sample_delay_h; i++)
-                       gpif_make_delay_state(pSTATE++, 0, 0x00, 0x00);
+                       gpif_make_delay_state(pSTATE++, 0, 0x00);
 
                if (cmd->sample_delay_l != 0)
-                       gpif_make_delay_state(pSTATE++, cmd->sample_delay_l, 0x00, 0x00);
+                       gpif_make_delay_state(pSTATE++, cmd->sample_delay_l, 0x00);
        }
 
        /* Populate S1 - the decision point. */
-       gpid_make_data_dp_state(pSTATE++);
+       gpif_make_data_dp_state(pSTATE++);
 
        /* Execute the whole GPIF waveform once. */
        gpif_set_tc16(1);