From: Joel Holdsworth <redacted>
Date: Sun, 11 Mar 2012 15:36:03 +0000 (+0000)
Subject: Fixed GPIF waveform branch, and annotated population code
X-Git-Tag: sigrok-firmware-fx2lafw-0.1.0~45
X-Git-Url: https://sigrok.org/gitaction?a=commitdiff_plain;h=baecf744abd88bde4e8badf5535872f58e3873d4;p=sigrok-firmware-fx2lafw.git

Fixed GPIF waveform branch, and annotated population code
---

diff --git a/gpif-acquisition.c b/gpif-acquisition.c
index 5a76fae5..b57bcf68 100644
--- a/gpif-acquisition.c
+++ b/gpif-acquisition.c
@@ -169,17 +169,51 @@ void gpif_acquisition_start(const struct cmd_start_acquisition *cmd)
 
 	/* Populate S0 */
 	pSTATE = &GPIF_WAVE_DATA;
+
+	/* DELAY
+	 * Delay cmd->sample_delay clocks.
+	 */
 	pSTATE[0] = cmd->sample_delay;
+
+	/* OPCODE
+	 * SGL=0, GIN=0, INCAD=0, NEXT=0, DATA=1, DP=0
+	 * Collect data in this state.
+	 */
 	pSTATE[8] = 0x02;
+
+	/* OUTPUT
+	 * OE[0:3]=0, CTL[0:3]=0
+	 */
 	pSTATE[16] = 0x00;
+
+	/* LOGIC FUNCTION
+	 * Not used
+	 */
 	pSTATE[24] = 0x00;
 
-	/* Populate S1 */
+	/* Populate S1 - the decision point */
 	pSTATE = &GPIF_WAVE_DATA + 1;
-	pSTATE[0] = 0x00;
-	pSTATE[8] = 0x01;
+
+	/* BRANCH
+	 * Branch to IDLE if condition is true, back to S0 otherwise
+	 */
+	pSTATE[0] = (7 << 3) | (0 << 0);
+
+	/* OPCODE
+	 * SGL=0, GIN=0, INCAD=0, NEXT=0, DATA=0, DP=1
+	 */
+	pSTATE[8] = (1 << 0);
+
+	/* OUTPUT
+	 * OE[0:3]=0, CTL[0:3]=0
+	 */
 	pSTATE[16] = 0x00;
-	pSTATE[24] = 0x36;
+
+	/* LOGIC FUNCTION
+	 * Evaluate if the FIFO full flag is set.
+	 * LFUNC=0 (AND), TERMA=6 (FIFO Flag), TERMB=6 (FIFO Flag)
+	 */
+	pSTATE[24] = (6 << 3) | (6 << 0);
 
 	/* Execute the whole GPIF waveform once */
 	gpif_set_tc16(1);