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Text File  |  1998-10-24  |  9KB  |  153 lines
  1. PRT_LINE ⑧x1k1                                חללללללללללללללללל†
  2.                                 ´     MC68901     ´
  3.                                 ´ bit assignments ´
  4.                                 זללללללללללללללללל¶
  5.                                  Motorola Corporation 68901
  6.                                  Multi-Fonction Peripheral
  7.  םגגגגגגגגגגגגגגגגגגגגגגגגגגגגגג™
  8.  ø General Purpose input output ø     b7=monochrom monitor                 (NOT)
  9.  ø Interrupt Port               ø     b6=auxiliary ring indicator          (NOT)
  10.  ø                              ø     b5=FDC/HDC                           (NOT)
  11.  ø                              ø     b4=MC6850_IKBD/MC6850_MIDI           (NOT)
  12.  ø                              ø     b3=blitter busy                      (NOT)
  13.  ø                              ø     b2=auxiliary clear to send           (NOT)
  14.  ø                              ø     b1=auxiliary data carrier detected   (NOT)
  15.  ø                              ø     b0=printer busy                      (NOT)
  16.  ijגגגגגגגגגגגגגגגגגגגגגגגגגגגגגגך
  17.          םגגגגגגגגגגגגגגגגגגגגגג™
  18.          ø Active Edge Register ø  b7-b0=(see GPIP)              (0:low  1:high)
  19.          ijגגגגגגגגגגגגגגגגגגגגגגך
  20.       םגגגגגגגגגגגגגגגגגגגגגגגגג™
  21.       ø Data Direction Register ø  b7-b0=(see GPIP)          (0:input  1:output)
  22.       ijגגגגגגגגגגגגגגגגגגגגגגגגגך
  23.   םגגגגגגגגגגגגגגגגגגגגגגגגגגגגג™                                 Priority  &
  24.   ø Interrupt Enable Register A ø                                 Vector [b3-b0]
  25.   ø                             ø     b7=monochrom monitor                 1111
  26.   ø                             ø     b6=auxiliary ring indicator          1110
  27.   ø                             ø     b5=timer A                           1101
  28.   ø                             ø     b4=auxiliary receive register full   1100
  29.   ø                             ø     b3=auxiliary receive error           1011
  30.   ø                             ø     b2=auxiliary transmit register empty 1010
  31.   ø                             ø     b1=auxiliary transmit error          1001
  32.   ø                             ø     b0=timer B                           1000
  33.   בגגגגגגגגגגגגגגגגגגגגגגגגגגגגגœ
  34.   ø Interrupt Enable Register B ø     b7=FDC/HDC                           0111
  35.   ø                             ø     b6=MC6850_IKBD/MC6850_MIDI           0110
  36.   ø                             ø     b5=timer C                           0101
  37.   ø                             ø     b4=timer D                           0100
  38.   ø                             ø     b3=blitter busy                      0011
  39.   ø                             ø     b2=auxiliary clear to send           0010
  40.   ø                             ø     b1=auxiliary data carrier detected   0001
  41.   ø                             ø     b0=printer busy                      0000
  42.   ø                             ø                          (0:disable  1:enable)
  43.   ijגגגגגגגגגגגגגגגגגגגגגגגגגגגגגך
  44. םגגגגגגגגגגגגגגגגגגגגגגגגגגגגגגג™
  45. øInterrupt Pending Register A/B ø  b7-b0=(see IERA/B)      (0:nothing 1:pending)
  46. ijגגגגגגגגגגגגגגגגגגגגגגגגגגגגגגגך
  47. םגגגגגגגגגגגגגגגגגגגגגגגגגגגגגגג™
  48. øInter. In Service Register A/B ø  b7-b0=(see IERA/B)   (0:nothing 1:in service)
  49. ijגגגגגגגגגגגגגגגגגגגגגגגגגגגגגגגך
  50.   םגגגגגגגגגגגגגגגגגגגגגגגגגגגגג™
  51.   ø Interrupt Mask Register A/B ø  b7-b0=(see IERA/B)    (0:masked 1:authorized)
  52.   ijגגגגגגגגגגגגגגגגגגגגגגגגגגגגגך
  53.               םגגגגגגגגגגגגגגגגג™
  54.               ø Vector Register ø  b7-b4=[b7-b4]=non auto-vector high
  55.               ø                 ø     b3=software interrupt mode
  56.               ø                 ø        0:automatic end of interrupt
  57.               ø                 ø        1:software  end of interrupt
  58.               ijגגגגגגגגגגגגגגגגגך
  59.    םגגגגגגגגגגגגגגגגגגגגגגגגגגגג™
  60.    ø Timer A/B Control Register ø     b4=reset
  61.    ø                            ø        0:no
  62.    ø                            ø        1:yes
  63.    ø                            ø  b3-b0=mode
  64.    ø                            ø        0000:stop
  65.    ø                            ø        0001:delay  fr./4
  66.    ø                            ø        0010:delay  fr./10
  67.    ø                            ø        0011:delay  fr./16
  68.    ø                            ø        0100:delay  fr./50
  69.    ø                            ø        0101:delay  fr./64
  70.    ø                            ø        0110:delay  fr./100
  71.    ø                            ø        0111:delay  fr./200
  72.    ø                            ø                   (frequency=2.4576 MHz)
  73.    ø                            ø        1000:event count
  74.    ø                            ø             (timer A input=printer busy  )
  75.    ø                            ø             (timer B input=display enable)
  76.    ø                            ø        1001:measure fr./4
  77.    ø                            ø        1010:measure fr./10
  78.    ø                            ø        1011:measure fr./16
  79.    ø                            ø        1100:measure fr./50
  80.    ø                            ø        1101:measure fr./64
  81.    ø                            ø        1110:measure fr./100
  82.    ø                            ø        1111:measure fr./200
  83.    ijגגגגגגגגגגגגגגגגגגגגגגגגגגגגך
  84.    םגגגגגגגגגגגגגגגגגגגגגגגגגגגג™
  85.    ø Timer C+D Control Register ø  b6-b4=timer C mode (see timer A/B b2-b0)
  86.    ø                            ø  b2-b0=timer D mode (see timer A/B b2-b0)
  87.    ø                            ø        (serial clock=timer D output)
  88.    ijגגגגגגגגגגגגגגגגגגגגגגגגגגגגך
  89.   םגגגגגגגגגגגגגגגגגגגגגגגגגגגגג™
  90.   ø Timer A/B/C/D Data Register ø  b7-b0=data
  91.   ijגגגגגגגגגגגגגגגגגגגגגגגגגגגגגך
  92. םגגגגגגגגגגגגגגגגגגגגגגגגגגגגגגג™
  93. øSynchronous Character Register ø  b7-b0=character
  94. ijגגגגגגגגגגגגגגגגגגגגגגגגגגגגגגגך
  95. םגגגגגגגגגגגגגגגגגגגגגגגגגגגגגגג™
  96. ø Universal                     ø     b7=serial frequency
  97. ø synchronous asynchronous      ø        0:frequency
  98. ø receiver transmitter          ø        1:frequency/16
  99. ø Control Register              ø  b6-b5=character size
  100. ø                               ø        00:8 bits
  101. ø                               ø        01:7 bits
  102. ø                               ø        10:6 bits
  103. ø                               ø        11:5 bits
  104. ø                               ø  b4-b3=frame
  105. ø                               ø           transmission    start-bit  stop-bit
  106. ø                               ø        00:synchronous          0         0
  107. ø                               ø        01:asynchronous         1         1
  108. ø                               ø        10:asynchronous         1         1.5
  109. ø                               ø        11:asynchronous         1         2
  110. ø                               ø     b2=parity
  111. ø                               ø        0:no
  112. ø                               ø        1:yes
  113. ø                               ø     b1=parity type
  114. ø                               ø        0:odd
  115. ø                               ø        1:even
  116. ijגגגגגגגגגגגגגגגגגגגגגגגגגגגגגגגך
  117.      םגגגגגגגגגגגגגגגגגגגגגגגגגג™
  118.      ø Receiver Status Register ø     b7=buffer  full               (0:no 1:yes)
  119.      ø                          ø     b6=overrun error              (0:no 1:yes)
  120.      ø                          ø     b5=parity  error              (0:no 1:yes)
  121.      ø                          ø     b4=frame   error (async.)     (0:no 1:yes)
  122.      ø                          ø     b3=found (sync.) / break     (async.)
  123.      ø                          ø        0:found         0:no detecded
  124.      ø                          ø        1:search        1:detected
  125.      ø                          ø     b2=match (sync.) / character (async.)
  126.      ø                          ø        0:no            0:nothing
  127.      ø                          ø        1:yes           1:in progress
  128.      ø                          ø     b1=synchronous strip
  129.      ø                          ø        0:disable
  130.      ø                          ø        1:enable
  131.      ø                          ø     b0=receiver
  132.      ø                          ø        0:disable
  133.      ø                          ø        1:enable
  134.      ijגגגגגגגגגגגגגגגגגגגגגגגגגגך
  135.   םגגגגגגגגגגגגגגגגגגגגגגגגגגגגג™
  136.   ø Transmitter Status Register ø     b7=buffer   empty             (0:no 1:yes)
  137.   ø                             ø     b6=underrun error             (0:no 1:yes)
  138.   ø                             ø     b5=auto turnaround            (0:no 1:yes)
  139.   ø                             ø     b4=end of transmission        (0:no 1:yes)
  140.   ø                             ø     b3=break (async.)             (0:no 1:yes)
  141.   ø                             ø  b2-b1=low and high bits
  142.   ø                             ø        00:high impedance
  143.   ø                             ø        01:low
  144.   ø                             ø        10:high
  145.   ø                             ø        11:high (loop back)
  146.   ø                             ø     b0=transmitter
  147.   ø                             ø        0:disable
  148.   ø                             ø        1:enable
  149.   ijגגגגגגגגגגגגגגגגגגגגגגגגגגגגגך
  150.           םגגגגגגגגגגגגגגגגגגגגג™
  151.           ø USART Data Register ø  b7-b0=data
  152.           ijגגגגגגגגגגגגגגגגגגגגגך
  153.