2–60
Table 2– 54. PC/104-Plus Expansion Bus Connector, P21 (A1-D30)

PinABCD

1 GND/5.0V KEY4Reserved +5 AD00
2 VI/O (+5V) AD02 AD01 +5V
3 AD05 GND AD04 AD03
4 C/BE0* AD07 GND AD06
5 GND AD09 AD08 GND
6 AD11 VI/O (+5V) AD10 M66EN1
7 AD14 AD13 GND AD12
8 +3.3V C/BE1* AD15 +3.3V
9 SERR* GND SB0* PAR
10 GND PERR* +3.3V SDONE
11 STOP* +3.3V LOCK* GND
12 +3.3V TRDY* GND DEVSEL*
13 FRAME* GND IRDY* +3.3V
14 GND AD16 +3.3V C/BE2*
15 AD18 +3.3V AD17 GND
16 AD21 AD20 GND AD19
17 +3.3V AD23 AD22 +3.3V
18 IDSEL0 GND IDSEL1 IDSEL2
19 AD24 C/BE3* VI/O (+5V) IDSEL3
20 GND AD26 AD25 GND
21 AD29 +5V AD28 AD27
22 +5V AD30 GND AD31
23 REQ0* GND REQ1* VI/O
24 GND REQ2* +5V GNT0*
25 GNT1* VI/O (+5V) GNT2* G ND
26 +5V CLK0 GND CLK1F
27 CLK2 +5V CLK3 GND
28 GND INTD* +5V RST*
29 +12V INTA* INTB* INTC*
30 -12V Reserved Reserved GND/3.3V KEY4
PCI Bus (P21) Notes
1. Signal M66EN is grounded on the motherboard (Ground = 33MHz bus speed ).