-
Notifications
You must be signed in to change notification settings - Fork 0
/
serialvector.ino
187 lines (151 loc) · 4.35 KB
/
serialvector.ino
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
/*
Simple program to receive lists of vertices over the serial port and display
them.
Protocol decoder is based on that used by http://trmm.net/v.st, and should be
more-or-less coompatible. Data is sent as 32-bit words, MSB-first, as follows:
31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
| flag | brightness | Y position | X position |
|2 bits| 6 bits | 12 bits | 12 bits |
The flag field is used as follows:
| Flag | Description |
|------|----------------------------------------------|
| 00 | Sync word, reset command parser |
| 01 | Terminator, send received vectors to display |
| 10 | Vector data |
| 11 | Unused |
Due to the lack of a brightness/blanking output, the brightness field is only
used to differentiate between line-drawing and invisible 'transit' vectors. A 0
brightness value moves the cursor without drawing a line, a nonzero value draws
a line from the current cursor position to the given coordinates.
To reset the protocol parser, send 4 or more 0 bytes in a row.
An example 'frame' of vector data is shown below, drawing a square in the center
of the display
00 00 00 00 Sync word
80 20 02 00 Move cursor to (512, 512)
BF E0 02 00 Draw line to (512, 3584)
BF E0 0E 00 Draw line to (3584, 3584)
BF 20 0E 00 Draw line to (3584, 512)
BF 20 02 00 Draw line to (512, 512)
01 01 01 01 Terminator
After the terminator is sent, the received vectors will be displayed
*/
#include "VectorGFX.h"
VectorGFX gfx;
void testPattern()
{
/* Square in bottom-left */
gfx.moveto(0, 0);
gfx.lineto(1024, 0);
gfx.lineto(1024, 1024);
gfx.lineto(0, 1024);
gfx.lineto(0, 0);
/* Fill square with starbust pattern */
gfx.moveto(0, 0);
for (unsigned j = 0; j <= 1024; j += 128)
{
gfx.lineto(1024, j);
gfx.moveto(0, 0);
gfx.lineto(j, 1024);
gfx.moveto(0, 0);
}
for (unsigned j = 0; j < 1024; j += 128)
{
gfx.lineto(j, 1024);
gfx.moveto(0, 0);
}
/* Triangle in bottom-right */
gfx.moveto(4095, 0);
gfx.lineto(4095 - 512, 0);
gfx.lineto(4095 - 0, 512);
gfx.lineto(4095, 0);
/* Square in top-right */
gfx.moveto(4095, 4095);
gfx.lineto(4095 - 512, 4095);
gfx.lineto(4095 - 512, 4095 - 512);
gfx.lineto(4095, 4095 - 512);
gfx.lineto(4095, 4095);
/* Hourglass in top-left */
gfx.moveto(0, 4095);
gfx.lineto(512, 4095);
gfx.lineto(0, 4095 - 512);
gfx.lineto(512, 4095 - 512);
gfx.lineto(0, 4095);
/* Center target */
gfx.moveto(2047, 2047 - 512);
gfx.lineto(2047, 2047 + 512);
gfx.moveto(2047 - 512, 2047);
gfx.lineto(2047 + 512, 2047);
}
int read_data(int c)
{
static uint32_t cmd;
static unsigned offset;
static unsigned rx_points;
static unsigned do_resync;
if (c < 0)
{
return -1;
}
// if we are resyncing, wait for a non-zero byte
if (do_resync)
{
if (c == 0)
return 0;
do_resync = 0;
}
cmd = (cmd << 8) | c;
offset++;
if (offset != 4)
{
return 0;
}
// we have a new command
// check for a resync
if (cmd == 0)
{
do_resync = 1;
offset = cmd = 0;
return 0;
}
unsigned flag = (cmd >> 30) & 0x3;
unsigned bright = (cmd >> 24) & 0x3F;
unsigned x = (cmd >> 12) & 0xFFF;
unsigned y = (cmd >> 0) & 0xFFF;
offset = cmd = 0;
rx_points++;
// bright 0, switch buffers
if (flag == 0)
{
// Attempt to detect and avoid blank screen condition
if (rx_points < 2)
{
rx_points = 0;
gfx.moveto(0, 0);
gfx.lineto(0, 4095);
gfx.lineto(4095, 4095);
gfx.lineto(4095, 0);
gfx.lineto(0, 0);
}
rx_points = 0;
gfx.display();
return 1;
}
rx_points++;
Vertex v = {.x = x, .y = y, .bright = bright};
gfx.addVertex(v);
return 0;
}
void setup()
{
Serial.begin(115200);
gfx.begin();
testPattern();
gfx.display();
}
void loop()
{
while (Serial.available())
{
read_data(Serial.read());
}
}