Product number (P/N): MM5765N,
Keywords/Tags: MM5765N
Date of intro: ~1975,
Classification: / Part / IC,
Info: This chip provides a convenient and inexpensive means of adding "learn mode" programmability to many NATIONAL SEMICONDUCTOR calculator chips.
It interfaces directly by simply adding a single static switch, four dynamic keys and a mean of displaying an alarm condition.
The monolithic MOS integrated circuit combines P-channel enhancement and depletion mode technologies to obtain low voltage and low power characteristics
necessary for economical battery-powered products.
The MM5765 is a dynamic key sequence programmer that memorizes any combination of key entries while in the Load Mode, then automatically plays back
the pro-grammed sequence as often as desired in the Run Mode.
Up to 102 characters can be stored in multiprogram sequence blocks. Each block, or program, can be executed individually or the operator can make the
decision to branch to specific programs, run each in series or perform intermediate calculations from the keyboard.
When programming in the Load Mode, the Delete key provides a convenient editing feature and the Halt key programs variable data entry points where
control is temporarily returned to the operator in the Run Mode.
Start and Skip keys control operation in both modes.
Synchronization with the calculator chip is accomplished by monitoring its Digit Output and Ready signals.
The digit signals give timing information while the Ready indicates status of the calculator and synchronizes the key entry interface between it and the MM5765.
Up to four switch inputs (10, K2, K3 and K4) and up to twelve digit lines are connected in parallel with the calculator switch and digit terminals that
scan the keyboard.
Keys stored in the MM5765 that are entered by selecting K1 through K4 are encoded simply as matrix positions, i.e., a particular switch input at a
specific digit time. Therefore it is the key matrix address that is stored and not the key function.
Used in: NOVUS: 4515 (version-2)