summaryrefslogtreecommitdiffstats
path: root/libtoprammer/bit/src/attiny26dip20/attiny26dip20.v
blob: 7c9ddffc94196cf6090e9ab144ef706014d1e447 (plain)
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
/*
 *   TOP2049 Open Source programming suite
 *
 *   Atmel Tiny26 DIP20
 *   FPGA bottomhalf implementation
 *
 *   Copyright (c) 2010 Michael Buesch <mb@bu3sch.de>
 *
 *   This program is free software; you can redistribute it and/or modify
 *   it under the terms of the GNU General Public License as published by
 *   the Free Software Foundation; either version 2 of the License, or
 *   (at your option) any later version.
 *
 *   This program is distributed in the hope that it will be useful,
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *   GNU General Public License for more details.
 *
 *   You should have received a copy of the GNU General Public License along
 *   with this program; if not, write to the Free Software Foundation, Inc.,
 *   51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 */

/* The runtime ID and revision. */
`define RUNTIME_ID	16'h0002
`define RUNTIME_REV	16'h01

module attiny26dip20(data, ale, write, read, zif);
	inout [7:0] data;
	input ale;
	input write;
	input read;
	inout [48:1] zif;

	// Read output-enable
	wire read_oe;
	// Signals to/from the DUT
	reg dut_oe, dut_wr, dut_xtal, dut_pagel_bs1;
	reg dut_xa0, dut_xa1_bs2;
	reg [7:0] dut_data;
	// Cached address value
	reg [7:0] address;
	// Cached read data
	reg [7:0] read_data;
	// Constant lo/hi
	wire low, high;

	assign low = 0;
	assign high = 1;

	always @(negedge ale) begin
		address <= data;
	end

	always @(posedge write) begin
		case (address)
		8'h10: begin
			/* Data write */
			dut_data <= data;
		end
		8'h11: begin
			/* Nothing */
		end
		8'h12: begin
			/* Control pin access */
			case (data[6:0])
			1: begin
				/* Unused */
			end
			2: begin
				dut_oe <= data[7];
			end
			3: begin
				dut_wr <= data[7];
			end
			4, 9: begin
				dut_pagel_bs1 <= data[7];
			end
			5: begin
				dut_xa0 <= data[7];
			end
			6, 10: begin
				dut_xa1_bs2 <= data[7];
			end
			7: begin
				dut_xtal <= data[7];
			end
			8: begin
				/* Unused */
			end
			endcase
		end
		8'h1B: begin
			/* Nothing */
		end
		8'h1D: begin
			/* Nothing */
		end
		endcase
	end

	always @(negedge read) begin
		case (address)
		8'h10: begin
			/* Data read */
			read_data[0] <= zif[21];
			read_data[1] <= zif[20];
			read_data[2] <= zif[19];
			read_data[3] <= zif[18];
			read_data[4] <= zif[15];
			read_data[5] <= zif[14];
			read_data[6] <= zif[13];
			read_data[7] <= zif[12];
		end
		8'h12: begin
			/* Status read */
			read_data[0] <= zif[36];	/* RDY */
			read_data[7:1] <= 0;
		end

		8'hFD: read_data <= `RUNTIME_ID & 16'hFF;
		8'hFE: read_data <= (`RUNTIME_ID >> 8) & 16'hFF;
		8'hFF: read_data <= `RUNTIME_REV;
		endcase
	end

	assign read_oe = !read && address[4];

	bufif0(zif[1], low, low);
	bufif0(zif[2], low, low);
	bufif0(zif[3], low, low);
	bufif0(zif[4], low, low);
	bufif0(zif[5], low, low);
	bufif0(zif[6], low, low);
	bufif0(zif[7], low, low);
	bufif0(zif[8], low, low);
	bufif0(zif[9], low, low);
	bufif0(zif[10], low, low);
	bufif0(zif[11], low, low);
	bufif0(zif[12], dut_data[7], !dut_oe);
	bufif0(zif[13], dut_data[6], !dut_oe);
	bufif0(zif[14], dut_data[5], !dut_oe);
	bufif0(zif[15], dut_data[4], !dut_oe);
	bufif0(zif[16], high, low);
	bufif0(zif[17], low, low);
	bufif0(zif[18], dut_data[3], !dut_oe);
	bufif0(zif[19], dut_data[2], !dut_oe);
	bufif0(zif[20], dut_data[1], !dut_oe);
	bufif0(zif[21], dut_data[0], !dut_oe);
	bufif0(zif[22], low, low);
	bufif0(zif[23], low, low);
	bufif0(zif[24], low, low);
	bufif0(zif[25], low, low);
	bufif0(zif[26], low, low);
	bufif0(zif[27], low, low);
	bufif0(zif[28], dut_wr, low);
	bufif0(zif[29], dut_xa0, low);
	bufif0(zif[30], dut_xa1_bs2, low);
	bufif0(zif[31], dut_pagel_bs1, low);
	bufif0(zif[32], high, low);
	bufif0(zif[33], low, low);
	bufif0(zif[34], dut_xtal, low);
	bufif0(zif[35], dut_oe, low);
	bufif0(zif[36], low, high);
	bufif0(zif[37], low, high);
	bufif0(zif[38], low, low);
	bufif0(zif[39], low, low);
	bufif0(zif[40], low, low);
	bufif0(zif[41], low, low);
	bufif0(zif[42], low, low);
	bufif0(zif[43], low, low);
	bufif0(zif[44], low, low);
	bufif0(zif[45], low, low);
	bufif0(zif[46], low, low);
	bufif0(zif[47], low, low);
	bufif0(zif[48], low, low);

	bufif1(data[0], read_data[0], read_oe);
	bufif1(data[1], read_data[1], read_oe);
	bufif1(data[2], read_data[2], read_oe);
	bufif1(data[3], read_data[3], read_oe);
	bufif1(data[4], read_data[4], read_oe);
	bufif1(data[5], read_data[5], read_oe);
	bufif1(data[6], read_data[6], read_oe);
	bufif1(data[7], read_data[7], read_oe);
endmodule
bues.ch cgit interface