Z89135 Datasheet, PDF (44/66 Pages) Zilog, Inc. – Low-Cost DTAD Controller

Z89135/136 (ROMless)
Low-Cost DTAD Controller
Zilog
(B)00, (B)01
(B)02, (B)03
(B)04, (B)05
(B)06, (B)07
(B)08, (B)09
(B)0A, (B)0B
(B)0C, (B)0D
(B)0E, (B)0F
(F)0C
D7, D1
Outgoing Registers
Incoming Registers
DSP Interrupt Control Register
EXT0
EXT1
EXT2
EXT3
EXT0
EXT1
EXT2
EXT3
EXT4
D/A and A/D Data Registers
D9
Analog Control Register
EXT5
D2
EXT6
Figure 30. Z8-DSP Interface
DSP-Z8 MAILBOX
To receive information from the DSP, the Z8 uses eight in-
coming registers which are mapped in the Z8 extended
Register File (Bank B, 08 to 0F). The DSP treats these as
four 16-bit registers that correspond to the eight incoming
Z8 registers (Figure 30).
Both the outgoing registers and the incoming registers
share the same DSP address (EXT3-EXT0).
The Z8 can supply the DSP with data through eight outgo-
ing registers mapped into both the Z8 Expanded Register
File (Bank B, Registers 00 to 07) and the external register
interface of the DSP. These registers are Read/Write and
can be used as general-purpose registers of the Z8. The
DSP can only read information from these registers. Since
the DSP uses a 16-bit data format and the Z8 an 8-bit data
format, eight outgoing registers of the Z8 correspond to
four DSP registers. The DSP can only read information
from the outgoing registers.
Note: The Z8 can read and write to ERF Bank B R00-R07,
Registers 08-0F are Read Only from the Z8.
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PRELIMINARY
DS97TAD0300