Specifications
PCIe/104 and PCI/104-Express Specification Revision 3.0 February 17, 2015 Page 2
A reduced feature set OneBank version does not implement the Bank 2 or Bank 3 connectors. Figure 1-2 shows the same
basic views with the OneBank connector.
PCI/104-Express Module
1-Bank Connector
Connector B
PCI – 120 Pin Connector
D1
C1
B1
A1
PCI Bus: 32 bit/33MHz
Connector A
PCI Express – 52 pin Connector
3.550 inches
(90.17 mm)
3.775 inches
(95.89 mm)
Bank 1
PCIe/104 Module
1-Bank Connector
Connector A
PCI Express – 52 pin Connector
3.550 inches
(90.17 mm)
3.775 inches
(95.89 mm)
Bank 1
Figure 1-2: OneBank Connector PCI/104-Express and PCIe/104 Board Layouts on 104 Form Factor
ISA bus backward compatibility can naturally and easily be achieved with the use of a PCI-to-ISA bridge peripheral
module (see Appendix A).
1.4. PCIe/104 Type 1 and Type 2
PCIe/104 is implemented by a pair of high-speed surface mount connectors. If the host CPU has top and bottom
connectors electrically connected together then the system can be built either stack-up or stack-down, but not both at the
same time. However, there is no requirement for the connector on the top of the host to be electrically connected to the
connector on the bottom of the host. This means that a PCIe/104 bus stacking up can be completely separate from
PCIe/104 bus going down. The specification does require all peripheral boards to be universal, so all peripheral boards
will work either above or below the CPU.
This specification defines two versions of the PCIe/104 connector pin out, Type 1 and Type 2. Type 1 is the same
versions 1.0 and 1.1 of the PCI/104-Express and PCIe/104 specification. Type 2 replaces the PCI Express x16 link with
two PCI Express x4 links, two USB 3.0, two SATA, LPC, and an RTC battery. The OneBank implementation is
compatible with the common Type 1 and Type 2 features. See Table 1-1 below for a comparison.
Table 1-1 Feature Summary
Feature Type 1 Type 2 OneBank
USB 2.0 2 2 2
SMB 1 1 1
PCIe x1 4 4 4
Power +3.3V, +5V, +12V +3.3V, +5V, +12V +3.3V, +5V
ATX Control Yes Yes Yes
PCIe x4 2
PCIe x16* 1
USB 3.0 2
SATA 2
LPC 1
RTC Battery 1
* x16 Link can be used as x8 or x4, see Section 2.4.1.1.
1.4.1 PCI/104-Express Version 1.0 and 1.1 Host Board Compatibility
All host boards built to PCI/104-Express version1.0 and 1.1 are considered Type 1.