CY750 Programmable Controller

Not for New Designs

Standard Features

• On-chip program storage
• 24 high-level instructions
• ASCII or binary commands
• 8 I/O lines may be set/tested/pulsed
• 8-bit I/O port plus 8-bit output port
• Simple handshake interface
• Program edit capability
• 16-bit up/down counter register
• Bit-testing branching
• Relative and absolute jumps
• Test-and-skip on flags and I/O lines
• Background timing
• Background counting
• Watchdog timer
• Easy interface to IEEE-488 or RS-232-C
• Send commands while excuting

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CY750 Overview

The CY750 provides the first truly intelligent general purpose I/O controller. The +5-volt, 40-pin device offers a simple handshake interface for 8-bit parallel loading of either ASCII or binary commands and data, and for binary readout of data and status, A high-level instruction set offers a powerful sequencing and testing mechanism that multiplies the power of any computer. Background timing or counting during program execution allows event monitoring and watchdog timeouts. A unique 'live' command feature allows commands to be issued while stored programs are executing.

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CY750 Command Summary

ASCII
Code    Name & Interpretation

Aa      ALTER           program counter, one byte relative branch
B       BACKGROUND      timer enable, status flag set on overflow
Cc      COUNT           c events in background, status flag set on cth count
Dd      DELAY           d x 100 µsec (0<d<64k)
Ee      EDIT            eth byte in program buffer
Ff      FALSE           branch on I/O line f or condition flag f, skip if 
                        false
Gg      GET             byte g to be tested, set all condition flags
H       HEXDATA         select binary mode
I       INITALIZE       software reset
Jj      JUMP            to byte j in program
Ll      LOW PORT        send 8-bit data / to port 1
Nn      NUMBER          n loaded into 16-bit register
Oo      OUTPUT          value 0 to 8-bit port 2
Pp      PULSE I/O       line p or test and reset status flag
Q       QUIT            entering/editing program code
Rr      RESET           line r or condition flag r
Ss      SET I/O         line s or condition flag s
Tt      TRUE            branch on I/O line t or condition flag t
                        skip if true
Vv      VALUE           v set in mask register
Ww      WATCHDOG        timeout enable, load w into 8-bit timer
X       EXECUTE         code in program buffer
+       INCREMENT       16-bit N-register, status flag set if overflow
-       DECREMENT       16-bit N-register, skip if zero
0       STOP            program, return to command mode

CY750 Pinout

1. WRITE/
2. XTAL
3. XTAL
4. RESET/
5. UNUSED
6. INTERRUPT/
7. GND
8. INSTROBE/
9. UNUSED
10. OUTSTROBE/
11. CLK/15
12. DB0
13. DB1
14. DB2
15. DB3
16. DB4
17. DB5
18. DB6
19. DB7
20. GND
21. P2.0
22. P2.1
23. P2.2
24. P2.3
25. RESERVED
26. + 5 VOLTS
27. P1.0/READY
28. P1.1
29. P1.2
30. P1.3
31. P1.4
32. P1.5
33. P1.6
34. P1.7
35. P2.4
36. P2.5
37. P2.6
38. P2.7
39. COUNTER INPUT/
40. + 5 VOLTS