# HG changeset patch
# User Mychaela Falconia <falcon@freecalypso.org>
# Date 1693474368 0
# Node ID b0524d1dc6eff4904d8f66a5278f5e1b18832215
# Parent  74330513121e99fd63c37182bab89a6fa969fbfe
simtrace3-sniff-dec: implement command decoding

diff -r 74330513121e -r b0524d1dc6ef sw/sniff-dec/command.c
--- a/sw/sniff-dec/command.c	Thu Aug 31 08:55:34 2023 +0000
+++ b/sw/sniff-dec/command.c	Thu Aug 31 09:32:48 2023 +0000
@@ -14,10 +14,138 @@
 extern unsigned rx_byte;
 extern int state;
 
+static char cmd_start_timestamp[18];
+static int cmd_start_line;
+static char data_start_timestamp[18];
+static int data_start_line;
+static char sw1_timestamp[18];
+static int sw1_line;
+
+static u_char cmd_hdr[5];
+static unsigned hdr_byte_count;
+static unsigned data_total, data_sofar, data_thistime;
+static u_char data_buf[256], sw1;
+
 void
 start_cmd_header()
 {
-	printf("input line %d: command header, end of implementation so far\n",
-		lineno);
-	exit(0);
+	strcpy(cmd_start_timestamp, linebuf);
+	cmd_start_line = lineno;
+	cmd_hdr[0] = rx_byte;
+	hdr_byte_count = 1;
+	state = STATE_CMD_HDR;
+}
+
+static void
+print_cmd_hdr()
+{
+	unsigned n;
+
+	printf("%s line %d: CMD", cmd_start_timestamp, cmd_start_line);
+	for (n = 0; n < 5; n++)
+		printf(" %02X", cmd_hdr[n]);
+	putchar('\n');
+}
+
+void
+cmd_hdr_byte_in()
+{
+	cmd_hdr[hdr_byte_count++] = rx_byte;
+	if (hdr_byte_count < 5)
+		return;
+	print_cmd_hdr();
+	if ((cmd_hdr[1] & 0xF0) == 0x60 || (cmd_hdr[1] & 0xF0) == 0x90) {
+		printf(" ERROR: INS byte is invalid!\n");
+		state = STATE_ERROR;
+		return;
+	}
+	if (cmd_hdr[4])
+		data_total = cmd_hdr[4];
+	else
+		data_total = 256;
+	data_sofar = 0;
+	state = STATE_CMD_PROC;
+}
+
+static void
+print_data()
+{
+	unsigned n;
+
+	printf("%s line %d: DATA\n", data_start_timestamp, data_start_line);
+	for (n = 0; n < data_sofar; n++) {
+		printf(" %02X", data_buf[n]);
+		if ((n & 15) == 15 || n == data_sofar - 1)
+			putchar('\n');
+	}
 }
+
+static void
+handle_sw1()
+{
+	strcpy(sw1_timestamp, linebuf);
+	sw1_line = lineno;
+	sw1 = rx_byte;
+	if (data_sofar)
+		print_data();
+	state = STATE_CMD_SW;
+}
+
+void
+handle_ack(single)
+{
+	if (data_sofar >= data_total) {
+		printf("%s line %d: ERROR: ACK for more data than possible\n",
+			linebuf, lineno);
+		state = STATE_ERROR;
+		return;
+	}
+	if (!data_sofar) {
+		strcpy(data_start_timestamp, linebuf);
+		data_start_line = lineno;
+	}
+	if (single)
+		data_thistime = 1;
+	else
+		data_thistime = data_total - data_sofar;
+	state = STATE_CMD_DATA;
+}
+
+void
+cmd_proc_byte_in()
+{
+	if (rx_byte == 0x60)
+		return;
+	if ((rx_byte & 0xF0) == 0x60 || (rx_byte & 0xF0) == 0x90) {
+		handle_sw1();
+		return;
+	}
+	if (rx_byte == cmd_hdr[1]) {
+		handle_ack(0);
+		return;
+	}
+	if (rx_byte == (cmd_hdr[1] ^ 0xFF)) {
+		handle_ack(1);
+		return;
+	}
+	printf("%s line %d: ERROR: invalid procedure byte\n", linebuf, lineno);
+	state = STATE_ERROR;
+}
+
+void
+cmd_data_byte_in()
+{
+	data_buf[data_sofar++] = rx_byte;
+	data_thistime--;
+	if (data_thistime)
+		return;
+	state = STATE_CMD_PROC;
+}
+
+void
+cmd_sw2_byte_in()
+{
+	printf("%s line %d: SW %02X %02X\n", sw1_timestamp, sw1_line, sw1,
+		rx_byte);
+	state = STATE_READY_FOR_CMD;
+}
diff -r 74330513121e -r b0524d1dc6ef sw/sniff-dec/dispatch.c
--- a/sw/sniff-dec/dispatch.c	Thu Aug 31 08:55:34 2023 +0000
+++ b/sw/sniff-dec/dispatch.c	Thu Aug 31 09:32:48 2023 +0000
@@ -143,6 +143,30 @@
 		extract_rx_byte();
 		pps_byte_in();
 		return;
+	case STATE_CMD_HDR:
+		if (check_parity())
+			return;
+		extract_rx_byte();
+		cmd_hdr_byte_in();
+		return;
+	case STATE_CMD_PROC:
+		if (check_parity())
+			return;
+		extract_rx_byte();
+		cmd_proc_byte_in();
+		return;
+	case STATE_CMD_DATA:
+		if (check_parity())
+			return;
+		extract_rx_byte();
+		cmd_data_byte_in();
+		return;
+	case STATE_CMD_SW:
+		if (check_parity())
+			return;
+		extract_rx_byte();
+		cmd_sw2_byte_in();
+		return;
 	default:
 		fprintf(stderr, "BUG in top state machine: invalid state\n");
 		abort();
diff -r 74330513121e -r b0524d1dc6ef sw/sniff-dec/state.h
--- a/sw/sniff-dec/state.h	Thu Aug 31 08:55:34 2023 +0000
+++ b/sw/sniff-dec/state.h	Thu Aug 31 09:32:48 2023 +0000
@@ -11,3 +11,6 @@
 #define	STATE_READY_FOR_CMD	5
 #define	STATE_PPS_MSG		6
 #define	STATE_CMD_HDR		7
+#define	STATE_CMD_PROC		8
+#define	STATE_CMD_DATA		9
+#define	STATE_CMD_SW		10