Lucent Technologies DSP1611, Information Manual

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Information Manual DSP1611/17/18/27/28/29 DIGITAL SIGNAL PROCESSOR
April 1998 Software Architecture
Lucent Technologies Inc.
DRAFT COPY
3-31
3.4 Interrupts
(continued)
3.4.2 Interrupt Sources (continued)
3.4.3 Outputs of Interrupts
The status bits in the ins register show if an interrupt has been recognized (defined as when the interrupt is latched
into the register). An interrupt, however, might be recognized but not serviced (acted on by executing the associ-
ated service routine) depending on the state of the machine (i.e., other interrupt in progress, uninterruptible instruc-
tion, etc.). An interrupt will not be serviced if not enabled. The VEC[3:0] outputs show the interrupt being serviced
(see the encoding in
Table 3-20 ). If no interrupt or trap is being serviced, the VEC[3:0] output pins are all zero.
Another output (IACK) goes high if any interrupt or trap is being serviced and goes low when the service routine
ends (see the functional timing diagrams for IACK timing).
Table 3-20. Vector Table
Source Vector Priority VEC[3:0]
†
† Pins VEC[3:0] are multiplexed with pins IOBIT[7:4]. Bit 12 of the ioc register must be cleared to enable VEC[3:0].
Issued by Cleared By
No interrupt — — 0x0 — —
Software interrupt 0x2 1 lowest 0x1 icall
‡
‡ The icall instruction is reserved for use by the hardware development system.
ireturn
IBF enabled by pioc
§
§ Available on DSP1617 only.
0x1 1 0x1 SIO in read of sdx
OBE enabled by pioc
§
0x1 1 0x1 SIO out write to sdx
PIDS enabled by pioc
§
0x1 1 0x1 PIO in read of pdx<0—7>
PODS enabled by pioc
§
0x1 1 0x1 PIO out write to pdx<0—7>
INT0 0x1 2 0x2 pin ireturn or write to ins
JINT 0x42 3 0x8 jtag in read of jtag
INT1 0x4 4 0x9 pin ireturn or write to ins
TIMEOUT 0x10 7 0xc timer ireturn or write to ins
IBF2 0x14 8 0xd SIO2 in read of sdx2
OBE2 0x18 9 0xe SIO2 out write to sdx2
Reserved 0x1c 10 — — —
EREADY
††
†† DSP1618/28 only.
0x20 11 0x1 ECCP ready ireturn or write to ins
EOVF
††
0x24 12 0x2 ECCP overflow ireturn or write to ins
Reserved 0x28 13 — — —
IBF enabled by inc 0x2c 14 0x3 SIO in read of sdx
OBE enabled by inc 0x30 15 0x4 SIO out write to sdx
PIDS/PIBF enabled by
inc
0x34 16 0x5 PHIF/PIO in read of pdx0
PODS/POBE enabled by
inc
0x38 17 0x6 PHIF/PIO out write to pdx0
TRAP from HDS 0x3 18 — breakpoint, jtag, or pin ireturn
TRAP from user 0x46 19 highest 0x7 pin ireturn