The RCBus is an extended version of the RC2014^TM bus, designed to overcome the limitations of the RC2014^TM bus. The bus extensions and formal specification have been developed by members of the retro-computing community via the retro-comp forum.

The RCBus specification v1.0 is available below.

RCBus forum: retro-comp google group.

The RCBus exists for these reasons:

• To overcome the limitations of the RC2014^TM bus whilst maintaining compatibility with existing products. The additions include support for advanced features, such as the Z80 interrupt priority chain, and support for other processor families.
• To help clarify what is a genuine RC2014^TM product and what is a product with a degree of compatibility to an RC2014^TM
• To reduce the chance of trademark infringement (RC2014 is a trademark belonging to RFC2795 Ltd)

The RC2014^TM bus specification is a subset of the full RCBus specification. This subset is defined by the RCBus-2014 specification. Similarly, the Z80 family extensions are defined by the RCBus-Z80 specification. Other processors and applications have their own extensions within the RCBus specification. Compatibility can be defined by which specifications are supported.

Modules designed for the 40-pin RCBus (or RC2014 standard bus) can be used with 80-pin RCBus backplanes, but not all 80-pin RCBus modules can be used with 40-pin RCbus/RC2014 backplanes.

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Notes relating to RCBus specification:

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RCBus Product Ranges

• SC700 series, 80-pin RCBus (extended RC2014 bus)
• SC600 series, 40-pin RCBus (RC2014 compatible)
• SC100 series, 40-pin+ RC2014 styling

RCBus Information

• I/O port addresses
• Photo gallery

RC2014 Information

• RC2014 Bus
• Circuit board dimensions, standard
• Modules list – updated 2019-04-09 (XLS)

RCBus Product Summary

There are a number of physical options in common use for RCBus products. These include:

Type	Row 1	Row 2	Profile	Bus spec.
80 pin	40 pins	40 pins	RCBus	RCBus 80 pin
40 pin	40 pins	n/a	RCBus	RCBus 40 pin
SP 40+	39 pins	10+ pins	RC2014 Standard	RC2014 Enhanced
SP 39	39 pins	n/a	RC2014 Standard	RC2014 Standard
LP 40	40 pins	n/a	RC2014 Low Profile	RC2014 Standard

Designs available on this site are shown below.

Backplanes	80 pin	40 pin	SP 40+	LP 40
6+1 slot, 5V in	SC701	SC671	n/a	n/a
6+1 slot	SC702	SC672 SC147	n/a	n/a
10+1 slot, 5V in	n/a	SC673	n/a	n/a
11+1, 12V in	n/a	SC133	n/a	n/a
12+1 slot, 5V in	SC709	n/a	n/a	n/a
12+1 slot	SC710	SC141	n/a	n/a
3 slot, 5V in	SC723	n/a	n/a	n/a
Z80 Motherboards	80 pin	40 pin	40+	LP
SCM+CP/M	SC720	SC114	n/a	n/a
RomWBW	SC720	n/a	n/a	n/a
Z180 Motherboards	80 pin	40 pin	40+	LP
SCM+CP/M	SC126	n/a	n/a	n/a
RomWBW	SC126	SC130	n/a	n/a
Power supply	80 pin	40 pin	40+	LP
8-15 volt	SC703	SC614	n/a	SC142
5 volt	SC712	n/a	n/a	SC149
Processor	80 pin	40 pin	40+	LP
Z80 CPU	SC706	SC601	SC153	SC149
Z80 SBC	SC708	n/a	SC108	n/a
Z80 + MMU	SC730	n/a	n/a	n/a
Z180 CPU	SC722	n/a	SC111	n/a
Memory	80 pin	40 pin	40+	LP
128kB RAM 128kB ROM	SC707	n/a	SC152	SC143 SC150 SC151
512kB RAM 512kB ROM	SC714	n/a	n/a	n/a
512kB RAM 512kB ROM x2	SC721	SC602	SC119	n/a
Storage	80 pin	40 pin	40+	LP
CF card	SC715 SC729	SC604 SC613	n/a	SC145
SD card	SC734	SC611	n/a	n/a
Serial	80 pin	40 pin	40+	LP
68B50	SC705	SC610 SC612	n/a	SC139
SIO	SC716	SC603	SC104 SC132	n/a
SIO+CTC	SC725	n/a	SC110	n/a
Digital	80 pin	40 pin	40+	LP
8 in, 8 out	SC719	SC605	SC129	SC134 SC135 SC136
PIO	SC717	n/a	SC103	n/a
Prototype	80 pin	40 pin	40+	LP
Prototyping	SC711 SC733 SC735 SC736	SC607	n/a	n/a
Breakout	SC724	n/a	SC115	n/a
Other	80 pin	40 pin	40+	LP
I2C master	SC704	SC608	n/a	SC137
CTC	SC718	n/a	SC102	n/a
Clock	SC726	n/a	n/a	n/a
RTC	SC727	SC606	n/a	n/a
Riser	SC728	n/a	n/a	n/a
PWM	SC731	n/a	n/a	n/a
Servo	SC732	SC609	n/a	n/a
Interrupt	SC737	n/a	n/a	n/a
Z80 Base systems	80 pin	40 pin	40+	LP
SCM+BASIC	SC720 SC794	SC114	n/a	SC192
SCM+CP/M	SC720 SC794	n/a	n/a	SC191 SC193
RomWBW	SC720 SC791 SC794	n/a	n/a	n/a
Z180 Base systems	80 pin	40 pin	40+	LP
SCM+BASIC	SC126 SC792	n/a	n/a	n/a
SCM+CP/M	SC126 SC792	n/a	n/a	n/a
RomWBW	SC126 SC792	SC130	n/a	n/a