IC203 - Sony CXD8514Q - Old 160pin GPU for use with Dual-ported VRAM
Unlike the later 208pin GPU's, the old 160pin GPU has less supply pins, and, it doesn't have a 24bit RGB output (nor any other video output at all), instead, it's used with a RGB D/A converter that reads the video data directly from Dual-ported VRAM (ie. special RAM chips with two data busses, one bus for GPU read/write access, and one for the RGB video output).
Code: Select all
1 VCC
2 GND
3 cpu 205 /GPU --- via 22 ohm
4 cpu 153 GPU.A2
5 cpu 204 /GRD --- via 22 ohm
6 cpu 203 /GWR --- via 22 ohm
7 cpu 202 DACK2 ---
8 cpu 76 /RES
9 VCC
10 GND/shield---
11 cpu 201 33MHzG --- via 22 ohm
12 VCC
13 GND/shield---
14 cpu 200 DREQ2 ---
15 cpu 102 /IRQ1 ---
16 cpu 159 HBLANK
17 cpu 199 VBLANK ---
18 ?
19 ?
20 VCC
21 GND
22 cpu 198 D31
23 cpu 197 D30
24 cpu 194 D29
25 cpu 193 D28
26 cpu 192 D27
27 cpu 191 D26
28 VCC
29 GND
30 cpu 190 D25
31 cpu 189 D24
32 cpu 188 D23
33 cpu 187 D22
34 cpu 186 D21
35 cpu 185 D20
36 VCC
37 GND
38 cpu 184 D19
39 cpu 181 D18
40 cpu 180 D17
----
41 cpu 179 D16
42 cpu 178 D15
43 VCC
44 GND
45 cpu 177 D14
46 cpu 176 D13
47 cpu 175 D12
48 cpu 174 D11
49 cpu 173 D10
50 GND
51 VCC
52 cpu 172 D9
53 cpu 169 D8
54 cpu 168 D7
55 cpu 167 D6
56 cpu 166 D5
57 cpu 165 D4
58 cpu 164 D3
59 GND
60 VCC
61 cpu 163 D2
62 cpu 162 D1
63 cpu 161 D0
64 GND
65 VCC
66 vram'a 27 A8'a
67 vram'a 28 A7'a
68 vram'a 29 A6'a
69 vram'a 30 A5'a
70 GND
71 vram'a 31 A4'a
72 vram'a 34 A3'a
73 vram'a 35 A2'a
74 vram'a 36 A1'a
75 vram'a 37 A0'a
76 GND
77 VCC
78 vram'a 60 D15'a
79 vram'a 58 D14'a
80 vram'a 55 D13'a
----
81 vram'a 53 D12'a
82 vram'a 50 D11'a
83 vram'a 48 D10'a
84 vram'a 45 D9'a
85 vram'a 43 D8'a
86 VCC
87 GND
88 vram'a 22 D7'a
89 vram'a 20 D6'a
90 vram'a 17 D5'a
91 vram'a 15 D4'a
92 vram'a 12 D3'a
93 vram'a 10 D2'a
94 vram'a 7 D1'a
95 vram'a 5 D0'a
96 VCC
97 vrams 41 DSF ---
98 vram'b 39 /CAS'b (via 22 ohm)
99 vram'a 39 /CAS'a (via 22 ohm)
100 VCC
101 GND
102 vram'b 2 DT/OE'b (via 22 ohm)
103 vram'a 2 DT/OE'a (via 22 ohm) ---
104 vrams 26 /RAS (via 100 ohm)
105 vram'a 2x /WE'a (via 100 ohm) (both /LWE and /UWE)
106 vram'b 2x /WE'b (via 100 ohm) (both /LWE and /UWE)
107 vrams 63 /SE (via 220 ohm) ---
108 vrams 64 SC (via 22 ohm) ---
109 VCC
110 GND
111 vram'b 60 D15'b
112 vram'b 58 D14'b
113 vram'b 55 D13'b
114 vram'b 53 D12'b
115 vram'b 50 D11'b
116 vram'b 48 D10'b
117 vram'b 45 D9'b
118 vram'b 43 D8'b
119 VCC
120 GND
----
121 vram'b 22 D7'b
122 vram'b 20 D6'b
123 vram'b 17 D5'b
124 vram'b 15 D4'b
125 vram'b 12 D3'b
126 vram'b 10 D2'b
127 vram'b 7 D1'b
128 vram'b 5 D0'b
129 VCC
130 GND
131 vram'b 27 A8'b
132 vram'b 28 A7'b
133 vram'b 29 A6'b
134 vram'b 30 A5'b
135 vram'b 31 A4'b
136 vram'b 34 A3'b
137 vram'b 35 A2'b
138 vram'b 36 A1'b
139 vram'b 37 A0'b
140 VCC
141 GND
142 OSC 53.20MHz
143 VCC
144 GND
145 cxa 6 ? --- via 220+2200 ohm "SCIN"
146 VCC
147 GND
148 cpu 160 DOTCLK via 22 ohm
149 VCC
150 GND
151 rgb 18 rgb.18 ---
152 rgb 20 rgb.20
153 rgb 21 rgb.21
154 rgb 19 rgb.19
155 cxa 10 /SYNC --- via 2200 ohm "SYNCIN"
156 ? maybe /VSYNC as in newer GPU
157 ? maybe /HSYNC as in newer GPU
158 VCC
159 GND
160 cpu 206 67MHzG via 22 ohm
This chip is used with the old 160pin GPU and two Dual-ported VRAM chips. The 2x16bit databus is capable of reading up to 32bits of VRAM data, and the chip does then extract the 15bit or 24bit RGB values from that data (depending on the GPU's current color depth).
The RGB outputs (pin 5,7,9) seem to be passed through transistors and capacitors... not sure how the capacitors could output constant voltage levels... unless the RGB signals are actually some kind of edge-triggering PWM pulses rather than real analog levels(?)
Code: Select all
1 ?
2 ?
3 Vxx
4 Vxx
5 RED via Transistor and Capacitor?? to RIN
6 Vxx
7 GREEN via Transistor and Capacitor?? to GIN
8 GND/shield
9 BLUE via Transistor and Capacitor?? to BIN
10 Vxx
11 ?
12 ?
13 ?
14 aGND ?
15 aGND ?
16 aGND ?
----
17 GND
18 gpu 151 gpu.151
19 gpu 154 gpu.154
20 gpu 152 gpu.152
21 gpu 153 gpu.153
22 gpu 148 DOTCLK via 22 ohm
23 GND
24 Vxx
25 vram'a 4 D0'a
26 vram'a 6 D1'a
27 vram'a 9 D2'a
28 vram'a 11 D3'a
29 vram'a 14 D4'a
30 vram'a 16 D5'a
31 vram'a 19 D6'a
32 vram'a 21 D7'a
----
33 vram'a 44 D8'a
34 vram'a 46 D9'a
35 vram'a 49 D10'a
36 vram'a 51 D11'a
37 vram'a 54 D12'a
38 vram'a 56 D13'a
39 vram'a 59 D14'a
40 GND
41 vram'a 61 D15'a
42 vram'b 4 D0'b
43 vram'b 6 D1'b
44 vram'b 9 D2'b
45 vram'b 11 D3'b
46 vram'b 14 D4'b
47 vram'b 16 D5'b
48 vram'b 19 D6'b
----
49 vram'b 21 D7'b
50 vram'b 44 D8'b
51 vram'b 46 D9'b
52 vram'b 49 D10'b
53 vram'b 51 D11'b
54 vram'b 54 D12'b
55 GND
56 Vxx
57 vram'b 56 D13'b
58 vram'b 59 D14'b
59 vram'b 61 D15'b
60 GND
61 GND
62 GND
63 ? --- testpoint?
64 GND
IC202 - 64pin NEC uPD482445LGW-A70-S or SEC KM4216Y256G-60 (VRAM 256Kx16)
These are special Dual-ported VRAM chips (with two data busses), the D0-D15 pins are wired to the GPU (for read/write access), the Q0-Q15 pins are wired to the RGB D/A converter (for sequential video output). The 8bit /LWE and /UWE write signals are shortcut with each other and wired to the GPU's 16bit /WE write signal.
Code: Select all
1 VCC
2 /DT/OE
3 GND
4 Q0
5 D0
6 Q1
7 D1
8 VCC
9 Q2
10 D2
11 Q3
12 D3
13 GND
14 Q4
15 D4
16 Q5
17 D5
18 VCC
19 Q6
20 D6
21 Q7
22 D7
23 GND
24 /LWE
25 /UWE
26 /RAS
27 A8
28 A7
29 A6
30 A5
31 A4
32 VCC
----
33 GND
34 A3
35 A2
36 A1
37 A0
38 QSF
39 /CAS
40 NC
41 DSF
42 GND
43 D8
44 Q8
45 D9
46 Q9
47 VCC
48 D10
49 Q10
50 D11
51 Q11
52 GND
53 D12
54 Q12
55 D13
56 Q13
57 VCC
58 D14
59 Q14
60 D15
61 Q15
62 GND
63 /SE
64 SC
Later 208pin GPUs are used with 'normal' DRAMs with single 32bit databus, the different video memory chips are looking as if there might be some timing differences between old and new GPUs.
The old 2x16bit VRAMs might be faster on accessing non-32bit-aligned memory addresses, and with the dual-ported vram they won't block GPU read/write access during RGB video output, so the old GPUs could be potentially faster - unless Sony optimized some other things in newer GPUs, then it might be vice versa.
Anyways, I have never did any GPU timing tests on the PSX hardware, neither for old GPUs nor new GPUs.
EDIT: See also http://www.psxdev.net/forum/viewtopic.php?f=70&t=1042 for decapped GPU pictures.