Faraday Electric FE3020 Data Buffer

The FE3030 is an 84-pin PLCC chip that forms part of the FE3400B chipset. It handles the data buffering between the 80286 processor and the PC/AT expansion bus as well as an 8-bit bus for on-board I/O peripherals (keyboard controller, etc)..

I don't have a datasheet for this component; the partial pinout described below was discovered by probing a GRiDCase 1520 laptop.

The "FE3001A AT Clock Generation and Cycle Control Device" manual has a block diagram (reproduced below) which references the FE3031 Data Buffer. I'm not sure what differences (if any) there are between the FE3030 and the FE3031.

Pin Assignments

XD3 XD2 XD1 XD0 GND VCC ED7 ED6 ED5 ED4 ED3 ED2 ED1 ED0 GND
11 10 9 8 7 6 5 4 3 2 1 84 83 82 81 80 79 78 77 76 75
VCC 12 FE3030 74 VCC
GND 13 73 GND
XD4 14 72
XD5 15 71
XD6 16 70
XD7 17 69
VCC 18 68 HLDA
GND 19 67 /MASTER
XD8 20 66
XD9 21 65
XD10 22 64 GND
XD11 23 63
VCC 24 62
GND 25 61
XD12 26 60 ADD0
XD13 27 59
XD14 28 58
XD15 29 57
/IOW 30 56
GND 31 55 GND
VCC 32 54 VCC
33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53
GND /IOR D0 D1 D2 VCC GND D3 D4 D5 D6 D7 D8 D9 D10 D11 D12 D13 D14 D15
Pin Purpose Direction Notes
6, 12, 18, 24, 32, 39, 54, 74 VCC Power input +5V DC
7, 13, 19, 25, 31, 33, 40, 55, 64, 73, 75 GND Signal ground Note that pins 33, 64, and 75 are the only ground pins not paired with a VCC pin; they may be signal pins that are strapped to ground.
8-11, 14-17, 20-23, 26-29 XD0-15 Output; likely input on /MASTER cycle PC/AT expansion bus data.
30 /IOW Maybe input from FE3000A? Can also be driven by expansion bus. Driven low (active) on all I/O write cycles. [TechRef 13-9]
34 /IOR Maybe input from FE3000A? Can also be driven by expansion bus. Driven low (active) on all I/O read cycles. [TechRef 13-10]
36-38, 41-53 D0-D15 Input; likely output on /MASTER cycle CPU data bus.
67 /MASTER Input Used by bus masters to take control of expansion bus.
68 /HLDA Input Hold acknowledge from 80286.
76-83 ED0-7 Input/output 8-bit data bus for onboard peripherals (e.g. keyboard controller).

Unknown Pins

Pin Notes
1 Connects to FE3000A, pin 3.
4 Connects to FE3000A, pin 16.
56 Connects to FE3000A, pin 45.
57 Connects to FE3000A, pin 82.
58 Connects to FE3000A, pin 46.
59 Connects to FE3000A, pin 11.
61 Connects to FE3010B, pin 58.
62 Connects to FE3000A, pin 75.
63 Connects to FE3000A, pin 47.
65 Connects to FE3000A, pin 55.
69 Connects to FE3000A, pin 51.
71 Connects to FE3000A, pin 76.
84 Connects to FE3000A, pin 3.
2, 3, 5, 35, 60, 66, 70, 72 Connections unknown.