External Bus, I/O, And On-Chip Peripherals - Motorola DSP56156 Manual

1.4

EXTERNAL BUS, I/O, AND ON-CHIP PERIPHERALS

Five on-chip peripherals are provided on the DSP56156: an 8-bit parallel Host MPU/DMA In-
terface, a 16-bit timer, two Synchronous Serial Interfaces (SSI1 and SSI0), and a sigma-del-
ta codec (see Figure 1-7). The DSP56156 provides 16 pins for an external address bus and
16 pins for an external data bus. These pins are grouped to form the Port A bus interface.
The DSP56156 also provides 27 programmable I/O pins. These pins may be used as gen-
eral purpose I/O pins or allocated to an on-chip peripheral. They are separate from the
DSP56156 codec, address buses, and data buses and are grouped as two I/O ports (B and
C).
Port B is a 15-pin I/O interface which may be used as general purpose I/O pins or as Host
MPU/DMA Interface pins. The Host MPU/DMA Interface provides a dedicated 8-bit paral-
1 - 18

EXTERNAL BUS, I/O, AND ON-CHIP PERIPHERALS

Table 1-6
Interrupt Sources Memory Map
Interrupt
Starting
Address IPL Interrupt Source
P:$0000 3 Hardware RESET
P:$0002 3 Illegal Instruction
P:$0004 3 Stack Error
P:$0006 3 Reserved
P:$0008 3 SWI
P:$000A 0-2 IRQA
P:$000C 0-2 IRQB
P:$000E 0-2 Reserved
P:$0010 0-2 SSI0 Receive Data with Exception
P:$0012 0-2 SSI0 Receive Data
P:$0014 0-2 SSI0 Transmit Data with Exception
P:$0016 0-2 SSI0 Transmit Data
P:$0018 0-2 SSI1 Receive Data with Exception
P:$001A 0-2 SSI1 Receive Data
P:$001C 0-2 SSI1 Transmit Data with Exception
P:$001E 0-2 SSI1 Transmit Data
P:$0020 0-2 Timer Overflow
P:$0022 0-2 Timer Compare
P:$0024 0-2 Host DMA Receive Data
P:$0026 0-2 Host DMA Transmit Data
P:$0028 0-2 Host Receive Data
P:$002A 0-2 Host Transmit Data
P:$002C 0-2 Host Command (default)
P:$002E 0-2 Codec Receive/Transmit
P:$0030 0-2 Available for Host Command
P:$0032 0-2 Available for Host Command
P:$0034 0-2 Available for Host Command
P:$0036 0-2 Available for Host Command
P:$0038 0-2 Available for Host Command
P:$003A 0-2 Available for Host Command
P:$003C 0-2 Available for Host Command
P:$003E 0-2 Available for Host Command
DSP56156 OVERVIEW MOTOROLA