Motorola DSP56012 1-18 DSP56012 Users Manual MOTOROLA

1-18 DSP56012 User’s Manual MOTOROLA
Overview
DSP56012 Architectural Overview
1.3.4.1 Parallel Host Interface (HI)
The parallel Host Interface (HI) is a byte-wide, full-duplex, double-buffered, parallel
port that can be connected directly to the data bus of a host processor. The host
processor can be any of a number of industry-standard microcomputers or
microprocessors, another DSP, or DMA hardware, because this interface looks like
static memory to the host processor. The HI is asynchronous and consists of two sets
of registers—one set accessible only to the host processor and a second set accessible
only to the DSP CPU (see Section 4, Parallel Host Interface).
1.3.4.2 Serial Host Interface (SHI)
The Serial Host Interface (SHI) provides a serial path for communication and
program/coefficient data transfers between the DSP and an external host processor
or other serial peripheral devices. This interface can connect directly to one of two
well-known and widely-used synchronous serial buses: the Serial Peripheral
Interface (SPI) bus defined by Motorola and the Inter Integrated-circuit Control (I2C)
bus defined by Philips. The SHI handles both SPI and I2C bus protocols as required
from a slave or a single-master device. In order to minimize DSP overhead, the SHI
supports single-, double-, and triple-byte data transfers. An optimal ten-word receive
FIFO register reduces the DSP overhead for data reception (see Section 5, Serial
Host Interface).
X:$FFDE DAX Control Register (XCTR)
X:$FFDD Reserved
X:$FFDC DAX Transmit Data Registers (XADRA/XADRB)
X:$FFDB Reserved
::
X:$FFC0 Reserved
Table 1-5 On-chip Peripheral Memory Map (Continued)
Address Register