R-Engine-D
Chapter 3: Hardware
3-1
Chapter 3:
Hardware
3.1
Am186ER
AND
RDC R1100
The R-Engine-D is compatible with two different CPUs. Both offer and support the same on-board
peripherals as well as the on the CPU itself, aside from a few differences. The Am186ER, from AMD, uses
times-four crystal frequency, while the R1100, from RDC, uses times-eight. The R-Engine-D uses a
10MHz system clock, giving the Am186ER a CPU clock of 40MHz and the R1100 a CPU clock of
80MHz. Both CPUs operate at +3.3V, with lines +5V tolerant. Secondly, the internal architectures are
different, with the Am186ER using x86 architecture, and the R1100 using the RISC architecture. Despite
the differing architectures, both CPUs offer nearly identical functionality.
3.2
Am186ER – Introduction
The Am186ER is based on the industry-standard x86 architecture. The Am186ER controllers are higher-
performance, more integrated versions of the 80C188 microprocessors. In addition, the Am186ER has new
peripherals. The on-chip system interface logic can minimize total system cost. The Am186ER has one
asynchronous serial port, one synchronous serial port, 32 PIOs, a watchdog timer, additional interrupt
pins, DMA to and from serial ports, a 16-bit reset configuration register, and enhanced chip-select
functionality.
In addition, the Am186ER has 32KB of internal volatile RAM. This provides the user with access to high
3.3
RDC R1100 – Introduction
The RDC 1100 is based on RISC internal architecture. It provides faster operation than the Am186ER,
3.4
Am186ER – Features
Clock
Due to its integrated clock generation circuitry, the Am186ER microcontroller allows the use of a times-
The R1100 offers times-eight crystal frequency, achieving 80MHz operation based on a 10MHz crystal.
The system CLKOUTA signal is routed to J1 pin 4, default 40 MHz. The CLKOUTB signal is not
CLKOUTA remains active during reset and bus hold conditions. The R-Engine-D initial function ae_init();
You may use clka_en(1); to enable CLKOUTA=CLK=J1 pin 4.
External Interrupts and Schmitt Trigger Input Buffer
There are six external interrupts: INT0-INT4 and NMI.
speed zero wait-state memory. In some instances, users can operate the R-Engine-D without external
SRAM, relying only on the Am186ER’s internal RAM.
allowing it to operate at up to 80MHZ, based a 10MHz system clock and times-eight crystal operation. The
RDC R1100 does not offer internal RAM like the Am186ER, so external SRAM is mandatory if using the
RDC R1100.
four crystal frequency. The design achieves 40 MHz CPU operation, while using a 10 MHz crystal.
connected in the R-Engine-D.
disables CLKOUTA and CLKOUTB with clka_en(0); and clkb_en(0);
