C 8 0 5 1 F 3 3 6 / 7 / 8 / 9
10
Rev. 0.3
5.5. Expansion I/O Connector (J1)
The 26-pin Expansion I/O connector J1 provides access to all signal pins of the C8051F338 device. Pins for +3 V,
digital ground and the output of an on-board low-pass filter are also available. A small through-hole prototyping
area is also provided. All I/O signals routed to connector J1 are also routed to through-hole connection points
between J1 and the prototyping area (see Figure 4 on page 6). Each connection point is labeled indicating the
signal available at the connection point. See Table 2 for a list of pin descriptions for J1.
5.6. Target Board DEBUG Interface (J4)
The DEBUG connector J4 provides access to the DEBUG (C2) pins of the C8051F338. It is used to connect the
Serial Adapter or the USB Debug Adapter to the target board for in-circuit debugging and Flash programming.
Table 3 shows the DEBUG pin definitions.
Table 2. J1 Pin Descriptions
Pin #
Description
Pin #
Description
1
+3 VD (+3.3 VDC)
14
P1.3
2
IDAC
15
P1.4
3
P0.0
16
P1.5
4
P0.1
17
P1.6
5
P0.2
18
P1.7
6
P0.3
19
P2.0
7
P0.4
20
P2.1
8
P0.5
21
P2.2
9
P0.6
22
P2.3
10
P0.7
23
P2.4
11
P1.0
24
/RST
12
P1.1
25
GND
13
P1.2
26
GND
Table 3. DEBUG Connector Pin Descriptions
Pin #
Description
1
+3 VD (+3.3 VDC)
2, 3, 9
GND (Ground)
4
P2.4/C2D
5
/RST (Reset)
6
P2.4
7
/RST/C2CK
8
Not Connected
10
USB Power (+5VDC from J4)
