Introduction
1-6
MC68360 USER’S MANUAL
MOTOROLA
1.2.3 Communications Processor Module (CPM)
The CPM contains features that allow the QUICC to excel in communications and control
applications. These features may be divided into three sub-groups:
Communications Processor (CP)
Two IDMA Controllers
Four General-Purpose Timers
The CP provides the communication features of the QUICC. Included are a RISC processor,
four SCCs, two SMCs, one SPI, 2.5 Kbytes of dual-port RAM, an interrupt controller, a time
slot assigner, three parallel ports, a parallel interface port, four independent baud rate gen-
erators, and fourteen serial DMA channels to support the SCCs, SMCs, and SPI.
The IDMAs provide two channels of general-purpose DMA capability. They offer high-
speed transfers, 32-bit data movement, buffer chaining, and independent request and
acknowledge logic. The RISC controller may access the IDMA registers directly in the buffer
chaining modes. The QUICC IDMAs are similar to, yet enhancements of, the two DMA chan-
nels found on the MC68340 and the one IDMA channel found on the MC68302.
The four general-purpose timers on the QUICC are functionally similar to the two general-
purpose timers found on the MC68302. However, they offer some minor enhancements,
such as the internal cascading of two timers to form a 32-bit timer. The QUICC also contains
a periodic interval timer in the SIM60, bringing the total to five on-chip timers.
1.3 UPGRADING DESIGNS FROM THE MC68302
Since the QUICC is a next-generation MC68302, many designers currently using the
MC68302 may wish to use the QUICC in a follow-on design. The following paragraphs
briefly discuss this endeavor in terms of architectural approach, hardware issues, and soft-
ware issues. See Section 9 Applications for further information.
1.3.1 Architectural Approach
The QUICC is the logical extension of the MC68302, but the overall architecture and philos-
ophy of the MC68302 design remains intact in the QUICC. The QUICC keeps the best fea-
tures of the MC68302, while making the changes required to provide for the increased
flexibility, integration, and performance requested by customers. Because the CPM is prob-
ably the most difficult module to learn, anyone who has used the MC68302 can easily
become familiar with the QUICC since the CPM architectural approach remains intact.
The most significant architectural change made on the QUICC was the translation of the
design into the standard M68300 family IMB architecture, resulting in a faster CPU and dif-
ferent system integration features.
Although the features of the SIM60 do not exactly correspond to those of the MC68302 SIM,
they are very similar. The QUICC SIM60 combines the best MC68302 SIM features with the
best MC68340 SIM features for improved performance.