PDP-8 mSeries Tester		wrs	2013_09_20

Parallel 
Port Pin	Name		Tester Usage

 1		C0- Control 0	SPARE_PIN_1
 2		D0+ Data 0	RESET_N
 3		D1+ Data 1	CS_N
 4		D2+ Data 2	SCK
 5              D3+ Data 3      chip A SI
 6              D4+ Data 4      chip B SI
 7              D5+ Data 5      chip C SI
 8              D6+ Data 6      chip D SI
 9              D7+ Data 7      chip E SI
10              S6+ -Ack        chip D S0
11              S7- +Busy       chip E SO
12              S5+ +PaperEnd   chip C SO
13              S4+ +SelectIn   chip B SO
14		C1- -AutoFd	SPARE_PIN_14
15              S3+ -Error      chip A SO
16		C2+ -Init	SPARE_PIN_16
17		C3- -Select	SPARE_PIN_17
18 thru 25	ground


In register order:

Parallel 
Port Pin	Name		Tester Usage

 1		C0- Control 0	SPARE_PIN_1
14		C1- -AutoFd	SPARE_PIN_14
16		C2+ -Init	SPARE_PIN_16
17		C3- -Select	SPARE_PIN_17

 2		D0+ Data 0	RESET_N
 3		D1+ Data 1	CS_N
 4		D2+ Data 2	SCK
 5              D3+ Data 3      chip A SI
 6              D4+ Data 4      chip B SI
 7              D5+ Data 5      chip C SI
 8              D6+ Data 6      chip D SI
 9              D7+ Data 7      chip E SI


15              S3+ -Error      chip A SO
13              S4+ +SelectIn   chip B SO
12              S5+ +PaperEnd   chip C SO
10              S6+ -Ack        chip D SO
11              S7- +Busy       chip E SO



Wiring for Microchip MCP23S17 16-bit GPIO expander

Pin     Name    Usage           Chip A  Chip B  Chip C  Chip D  Chip E

 1      GPBO    I/O pin
 2      GPB1    I/O pin
 3      GPB2    I/O pin
 4      GPB3    I/O pin
 5      GPB4    I/O pin
 6      GPB5    I/O pin
 7      GPB6    I/O pin
 8      GPB7    I/O pin
 9      VDD     3.7v
10      VSS     Ground
11      CS-N	PPort D1+   
12      SCK	PPort D2+
13      SI      PPort           D3+     D4+     D5+     D6+     D7-     
14      SO      PPort           S3+     S4+     S5+     S6+     S7+

15      A0	PPort D0+
16      A1	PPort D0+
17      A2	PPort D0+
18      RESET-N	PPort D0+
19      INTB	n.c.
20      INTA	n.c.
21      GPA0    I/O pin
22      GPA1    I/O pin
23      GPA2    I/O pin
24      GPA3    I/O pin
25      GPA4    I/O pin
26      GPA5    I/O pin
27      GPA6    I/O pin
28      GPA7    I/O pin




Power for Microchip MCP23S17 16-bit GPIO expander is about 3.6v
(+5v, 2 series diodes).

LEDs:
   ???, +3.6V (from +5v raw).
   ???, +5v UUT.
   ???, 'LED?'
   ???, 'LED?'
   ???, 'LED?'
   ???, 'LED?'

4 spare inputs/outputs are for strobes/probes (someday).

4 resistive loads:
     H   5.6K to ground           @2.4v, about  -420 uA (7400 spec:  -400A).
    3H   2.0K to ground           @2.4v, about -1200 uA (7440 spec: -1200uA).
     L   280 (560 || 560) to +5v  @0.4v, about 16 ma (7400 spec: 16 ma).
    3L    90 (180 || 180) to +5v  @0.4v, about 51 ma (7440 spec: 48 ma).

last line.