ez80190 ZiLOG Semiconductor, ez80190 Datasheet - Page 130

• Manufacturer Part Number: ez80190
• Description: Ez80190 Microprocessor
• Manufacturer: ZiLOG Semiconductor

PS006613-0306
EMPTY
DATA
Bank
Current State
CALC Bank Status
MACC_STAT[3:2]
00b
01b
10b
11b
EMPTY
CALC
Bank
The combination of possible status values for the DATA and CALC banks define
operating states for the MACC. The MACC progresses between states as new
calculations are defined, running calculations are completed, results are read, etc.
All possible MACC states, the next states possible, and the operation that causes
such a state transition are indicated in
Table 59. State Progression of the MACC During Operation
Operation
1. Define a new calculation by loading the MACC
2. Any write to MACC_AC4 produces the same
control registers using the OTI2R instruction.
When the OTI2R instruction completes and the
final write is to either MACC_CTL or any byte of
MACC_ACx, the banks swap and a new
calculation begins. The CALC bank status
changes from EMPTY to IN PROGRESS as it
begins the new calculation.
effect.
Table 58. MACC CALC Bank Status Codes
Description
The CALC bank is EMPTY. No calculation is set up for
execution.
Invalid.
The CALC bank is IN PROGRESS. MACC is currently
executing the operation defined by the CALC bank control
registers.
The CALC bank is DONE. The MACC has completed
execution of the operations defined by the CALC bank
control registers. The result is stored in the CALC bank
accumulator registers. The CALC bank must be swapped
with the DATA bank to allow the CPU to access the result.
Depending upon the full MACC status, this swap may occur
automatically.
PRELIMINARY
Table
59.
eZ80190 Product Specification
EMPTY
DATA
Bank
Next State
Multiply-Accumulator
PROGRESS
CALC
Bank
IN
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