Spectrum Digital eZdsp R2812 USB Technical Reference page 21

The definition of P2, which has the I/O signal interface is shown below.
Table 5: P2, Expansion Interface Connector
Pin # Signal
1 +3.3V/+5V/NC *
3
5
7
9
11
13 XD10
15 XD12
17 XD14
19
21
23
25
27
29 XA10
31 XA12
33 XA14
35
37 XZCS0AND1n
39 XREADY
41 XRnW
43
45 +3.3V
47 XRSn/RSn
49
51
53 XA16
55 XA18
57 XHOLDAn
59 No connect
* Default is No Connect (NC). User can jumper to +3.3V or +5V on backside of eZdsp
with JP5.
Pin #
2
XD0 4
XD2 6
XD4 8
XD6 10
XD8 12
14
16
18
XA0 20
XA2 22
XA4 24
XA6 26
XA8 28
30
32
34
GND 36
38
40
42
XWE 44
46
48
GND 50
GND 52
54
56
58
60
Spectrum Digital, Inc
Signal
+3.3/+5V/NC *
XD1
XD3
XD5
XD7
XD9
XD11
XD13
XD15
XA1
XA3
XA5
XA7
XA9
XA11
XA13
XA15
GND
XZCS2n
10K Pull-up
10K Pull-up
XRDn
XNMI/INT13
No connect
GND
GND
XA17
XHOLDn
No connect
No connect
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