4-40 DSP56012 User’s Manual MOTOROLA

Parallel Host Interface
Host Interface (HI)

Figure 4-15 Interrupt Vector Register Read Timing

Figure 4-16 HI Interrupt Structure

3. When HOREQ and HACK are asserted simultaneously,
the contents of the IVR are placed on the host data bus.
2. The host processor asserts HACK with its interrupt
acknowledge cycle.
1 K
DSP56012
IPL2
IPL1
IPL0
D0–D7
HOREQ
HACK
H0–H7
IACK
LOGIC
$0F
$3
+5 V
Interrupt Vector Number Interrupt Vector Register (IVR)
(Read/Write)
MC68000 1. The DSP56012 Asserts HOREQ to interrupt the host
processor.
IACK
Interrupt
Vector
Register
(IVR)
AA0323.11
70
AS
FC0–FC2
A1–A31
HOREQ Asserted HOREQ
AA0324k
Status
$2
Mask
HOREQ HF3 HF2 TRDY TXDE RXDF
70
0DMA
ICR
$3 INIT HF1 HF0 0 TREQ RREQ
70
HM0HM1
ISR interrupt Source