FLIP CHIP details

Here are detailed descriptions of FLIP CHIPs:

M167

This is a 8-bit comparator; it compares the value of two 8-bit numbers and provides four outputs which provide the relationships between those two numbers (A=B, A>B, A>=B, and B>=A). An EQUAL IN input, on pin U2, is provided for cascading them.

Inputs (bits numbered in PDP-11 style, with LSB = bit 0):

Input	Pin	Input	Pin
A7	F2	B7	H2
A6	H1	B6	S1
A5	E2	B5	D2
A4	F1	B4	E1
A3	C1	B3	D1
A2	J1	B2	M1
A1	K1	B1	M2
A0	B1	B0	A1

Outputs:

Pin	Signal
P1	EQUAL OUT (L)
R1	EQUAL OUT (H)
V1	A>B (H)
U1	B>=A (H)
L1	A>=B (H)

M203

This contains eight R/S flip flops. They are formed from a pair of NAND gates interconnected in the usual fashion; they provide inverted S and R inputs, and normal and inverted outputs.

M225

This is a 16x16-bit scratchpad memory; this card is used in the KA11 processor of the PDP-11/20, and is documented there.

In addition to 16-bit wide input and output, and byte write controls, it also provides an 4 sets of the 4 address inputs, and 4 inputs to select the desired set of address input. (I.e. the address lines are binary encoded, but the address select lines are not.) An internal 4-way mux selects the desired set of address inputs.

Data pins:

Input	Pin	Output	Pin
I00	AF2	O00	AE1
I01	AA1	O01	AC1
I02	AK2	O02	AL1
I03	AH1	O03	AJ1
I04	AE2	O04	AF1
I05	AD2	O05	AD1
I06	AJ2	O06	AM1
I07	AH2	O07	AK1
I08	BR2	O08	BM2
I09	BL1	O09	BM1
I10	BV2	O10	BU1
I11	BP1	O11	BR1
I12	BP2	O12	BT2
I13	BN2	O13	BN1
I14	BU2	O14	BV1
I15	BS2	O15	BS1

There may be a certain amount of variance between which pin is used for which bit; since the card is purely memory, the bits can be re-ordered without harm.

Control pins:

Address set select	Pin	Address set A	Pin	Address set B	Pin	Address set C	Pin	Address set D	Pin
A0	BE1	AA0	BF2	AB0	BH1	AC0	BE2	AD0	BF1
A1	BJ1	AA1	BD1	AB1	BD2	AC1	BC1	AD1	BA1
A2	AP2	AA2	AV2	AB2	AV1	AC2	AU1	AD2	AU2
A3	AS1	AA3	AT2	AB3	AS2	AC3	AR2	AD3	AR1

Pin BK1 is 'WRITE 15/8', and pin AM2 is 'WRITE 7/0'.

In addition, pin AN1 is a control input of some sort, but it is not yet clear what it does. It is possible that it is some sort of 'output enable'.

M240

This contains six R/S flip flops. They are formed from a pair of NAND gates interconnected in the usual fashion; they provide inverted S and R inputs, and normal and inverted outputs. They differ from the standard SR flops (in the M203, above) in that they have two set inputs.

M602

This is a dual pulse amplifier. It produces a negative-going pulse (nominally 50 nsec wide), triggered by an input transitioning from high to low; the input is a triple-input OR with inverting inputs.

External links

• FlipChip Modules