Pen control system for an automatic x-y plotter

Claim 2

In the combination including a cyclically operable digital calculator and an X-Y plotter having a positionable writing stylus, a system for controlling said writing stylus comprising: means for controlling the X-Y position of said writing stylus; gating means for selectively transferring data from said calculator to said stylus position controlling means; decoding means for providing first and second plot control signals in response to predetermined signals from said calculator; means responsive to either one of said first and second plot control signals from said decoding means for controlling said gating means to transfer a block of data to said st stylus position controlling means; memory means coupled to said decoding means for holding one of said first and second plot control signals in storage until the next plot control signal is provided by said decoding means; and means for enabling said stylus into a writing mode in response to said first plot control signal from said memory means after said stylus has been caused to move to an X-Y position determined by said block of data transferred to said X-Y position controlling means, and for disabling said stylus into a nonwriting mode in response to said second plot control signal from said memory means whenever said stylus is not moving.

Claim 3

The system of claim 1, wherein: said gating means includes means providing a transfer signal after a block of data has been transferred from said calculator to said stylus position controlling means; said enabling and disabling means includes: first gating means for providing a stylus enabling signal in response to the coincident occurrence of said transfer signal and said first plot control signal from said memoRy means; second gating means for providing a stylus disabling signal in response to said second plot control signal from said memory means; memory means for holding said stylus enabling signal from said first gating means in storage while said stylus is being moved in response to signals from said X-Y stylus position controlling means; means for transmitting said stylus enabling signal from said last named memory means and said stylus disabling signal from said second gating means to said stylus controlling means.

Claim 4

The system of claim 2, further including means for inhibiting said stylus enabling and disabling signals during the time interval that said stylus is moving under control of said X-Y stylus position controlling means.

Claim 5

The system of claim 2, further including electromechanical transducer means for driving said stylus into a writing or a nonwriting condition; and wherein said means for transmitting said stylus enabling and disabling signals includes bistable means having first and second output states for controlling said electromechanical transducing means to maintain said stylus in said writing or nonwriting condition, respectively, said first output state being operable in response to the enabling signal from said memory means of said enabling and disabling means, and said second state being operable in response to the disabling signal from said second gating means.

Claim 6

In the combination including a cyclically operable digital calculator and an X-Y plotter having a positionable pen, a system for controlling the various writing status of said pen comprising: means for controlling the X-Y position of said pen; means for gating data from said calculator to said pen position controlling means; decoding means responsive to first and second predetermined code signals from said calculator for providing first and second pen write control signals respectively; means responsive to either one of said first and second pen write control signals for controlling said gating means to transfer a block of data to said pen position controlling means; first memory means for storing said first and second pen write control signals as they are received from said decoding means; second memory means responsive to said first memory means for storing said first pen write control signal after a block of data has been transferred from said calculator to said pen position controlling means; third memory means for maintaining said pen in an enabled or a disabled condition in response to said first pen write control signal from said second memory means or to said second pen write control signal from said first memory means, respectively; and means for inhibiting reception of said first or second pen write control signals by said third memory means when said pen is moving in response to X-Y signals from said pen position controlling means.

Claim 7

In the combination including a cyclically operable digital calculator and an X-Y plotter having a positionable pen, a system for controlling the various writing status of said pen comprising: means for controlling the X-Y position of said pen; means for gating data from said calculator to said pen position controlling means; decoding means responsive to first and second predetermined code signals from said calculator for providing first and second pen write control signals respectively; means responsive to either one of said first and second pen write control signals for controlling said gating means to transfer a block of data to said pen position controlling means; first memory means for storing said first and second pen write control signals as they are received from said decoding means; second memory means responsive to said first memory means for storing said first pen write control signal after a block of data has been transferred from said calculator to said pen position controlling means; third memory means for maintaining said pen in an enabled or a disabled condition in response to said first pen write control signal from said second memory means or to said second pen write control signal from said first memory means, respectively; and means for inhibiting reception of said first or second pen write control signals by said third memory means when said pen is moving in response to X-Y signals from said pen position controlling means.

Claim 8

The system of claim 5, wherein: said gating means includes means for indicating when a block of data has been transferred to said pen position controlling means; said first memory means includes a flip-flop having complementary set and reset states corresponding respectively to said first and second pen write control signals; said second memory means includes: a flip-flop having set and reset states; means responsive to the coincident occurrence of signals from said indicating means and said set state of said first name flip-flop for setting said last named flip-flop to its set state; and said third memory means includes a flip-flop operable in a set state in response to signals from the flip-flop of said second memory means, and operable in a reset state in response to the reset state of the flip-flop of said first memory means.

Claim 9

The system of claim 6, wherein said means for controlling said gating means includes a flip-flop which is operable in a set state while a block of data is being transferred from said calculator to said pen position controlling means, and operable in a reset state when no data is being transferred to said pen position controlling means.

Claim 10

The system of claim 7 further including stopping means responsive to a stop signal for disabling said pen.

Claim 11

The system of claim 8, wherein said stopping means includes: means for conditioning each and every one of said flip-flops in its reset state; and means coupled to said pen position controlling means for returning said pen to a predetermined zero origin position.