User`s manual

26 RabbitCore RCM2000
Header J2
1–13 A[12:0] Output Rabbit 2000 address bus
14 STAT Output (Status) Output
15 PC0 Output TXD
16 PC1 Input RXD
17 PC2 Output TXC
18 PC3 Input RXC
19 PC4 Output TXB
20 PC5 Input RXB
21 PC6 Output TXA
22 PC7 Input RXA
21 PC6 Output TXA
Connected to program-
ming port
22 PC7 Input RXA
23–26 PD[0:3]
Bitwise or parallel
programmable I/O, can be
driven or open-drain output
16 mA sourcing and
sinking current at full AC
switching speed
27 PD4 ATXB output
28 PD5 ARXB input
29 PD6 ATXA output
30 PD7 ARXA input
31, 40 GND
32, 39 VCC
33 VBATR 3 V battery input
34 VRAM 2.1 V output 100 kΩ minimum load
35–36
SMODE0,
SMODE1
(0,0)—start executing at
address zero
No programming cable
attached
SMODE0 =1, SMODE1 = 1
Cold boot from asynchro-
nous serial port A at 2400
bps (programming cable
connected)
(0,1)—cold boot from slave
port
(1,0)—cold boot from
clocked serial port A
With programming cable
attached
37 /RES_OUT Reset Output
38 /RES_IN Reset Input
Table 2. RCM2000 Pinout Configurations (continued)
Pin Pin Name Default Use Alternate Use Notes