Acer 390 Series, Руководство по обслуживанию

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2-54 Service Guide
Table 2-6 FDC37C67 Pin Descriptions
Pin No./QFP Pin Name Type Symbol Buffer Type
78 Paper End 1 PE I
77 Printer Selected 1 SLCT I
81 Error at Printer 1 nERROR I
Keyboard/Mouse Interface (6)
56 Keyboard Data . 1 KDAT IOD16P
57 Keyboard Clock 1 KCLK IOD16P
58 Mouse Data 1 MDAT IOD16P
59 Mouse Clock 1 MCLK IOD16P
63 Keyboard Reset 1 KBDRST(Note 3) O4
64 Gate A20 1 A20M O4
Note 0: The interrupt request is output on one of the IRQx signals as an 024 buffer type. If EPP or ECP
Mode is enabled, this output is pulsed low, then released to allow sharing of interrupts. In this case, the
buffer type is OD24. Refer to the configuration section for more information.
Note 1: For 1 2it addressing, SAO:SA11 only, nCS should be tied to GND. For 1 6it external address
qualification, address bits SA11:SA15 can be "ORed" together and applied to nCS. The nCS pin functions
as SA11 in full 1 6it Internal Address Qualification Mode.CR24.6 controls the FDC37C67x addressing
modes.
Note 2: The "n" as the first letter of a signal name indicates an "Active Low" signal.
Note 3: KBDRST is active low.
BUFFER TYPE DESCRIPTIONS
•
I Input, TTL compatible.
•
IS Input with Schmitt trigger.
•
IOD16P Input/Output, 1 6mA sink, 90uA pullup. 0
•
IO24 Input/Output, 24mA sink, 1 2mA source.
•
IO4 Input/Output, 4mA sink, 2mA source.
•
O4 Output, 4mA sink, 2mA source.
•
O24 Output, 24mA sink, 1 2mA source.
•
OD24 Output, Open Drain, 24mA sink.
•
ICLK Clock Input