DESCRIPTION OF PIN FUNCTIONS
PIN NO. | NAME | SYMBOL | TYPE | DESCRIPTION |
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16 | n16 Bit | nMIS16 | I with pullup | Input. When low, it indicates a 16 bit modem, |
| Modem |
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| otherwise the modem is 8 bit wide. Used to |
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| determine if nIOIS16 (PCMCIA) and nIOCS16 |
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| (ISA) need to be asserted for modem cycles. |
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| The value of this pin may change from cycle |
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| to cycle. |
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110 | EEPROM | EESK | O4 | Output. 4μs clock used to shift data in and out |
| Clock |
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| of the serial EEPROM. |
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109 | EEPROM | EECS | O4 | Output. Serial EEPROM chip select. |
| Chip Select |
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108 | EEPROM | EEDO/ | O4 | Output. Connected to the DI input of the serial |
| Data Out | SDOUT |
| EEPROM. |
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107 | EEPROM | EEDI | I with pull- | Input. Connected to the DO output of the |
| Data In |
| down | serial EEPROM. |
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103, | I/O Base |
| I with pullup | Input. External switches can be connected to |
105, 106 |
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| these lines to select between predefined |
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| EEPROM configurations. The values of these |
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| pins are readable. These pins are used in ISA |
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| mode only. If in PCMCIA mode, these pins |
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| are not used. |
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9 | nTransmit | nTXLED | OD16 | Internal ENDEC - Transmit LED output. |
| LED |
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| nTransmit | nTXEN | O162 | External ENDEC - Active low Transmit |
| Enable |
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| Enable output. |
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12 | nRoard | nBSELED | OD16 | Internal ENDEC - Board Select LED activated |
| Select LED |
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| by accesses to I/O space (nIORD or nIOWR |
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| active with AEN low and valid address decode |
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| for ISA, and with nREG low and and “Enable |
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| Function” bit in the ECOR register is high for |
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| PCMCIA). The pulse is stretched beyond the |
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| access duration to make the LED visible. |
| Receive | RXD | I with pullup | External ENDEC - NRZ receive data input. |
| Data |
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| 14 |
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