Difference between revisions of "CIO Registers (Detailed)"

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(CIO Registers)
Line 17: Line 17:
 
               1=Right Justify (A0 from AD0)
 
               1=Right Justify (A0 from AD0)
 
   0          Reset (Caution: If set, requires a 3rd write to resurrect)
 
   0          Reset (Caution: If set, requires a 3rd write to resurrect)
 +
 +
----
  
 
* Control Register 01h - Master Configuration Control Register (R/W)
 
* Control Register 01h - Master Configuration Control Register (R/W)
Line 26: Line 28:
 
   2  PAE      Port A Enable
 
   2  PAE      Port A Enable
 
   0-1 LC      Counter/Timer Link Controls (see below)
 
   0-1 LC      Counter/Timer Link Controls (see below)
 +
 +
----
  
 
* Counter/Timer Link Controls values are:
 
* Counter/Timer Link Controls values are:
Line 32: Line 36:
 
   2=Counter/Timer 1's /OUTPUT does Trigger Counter/Timer 2
 
   2=Counter/Timer 1's /OUTPUT does Trigger Counter/Timer 2
 
   3=Counter/Timer 1's /OUTPUT is Counter/Timer 2's Count Input
 
   3=Counter/Timer 1's /OUTPUT is Counter/Timer 2's Count Input
 +
 +
----
  
 
* Control Register 20h - Port A Mode Specification Register (R/W)
 
* Control Register 20h - Port A Mode Specification Register (R/W)
Line 42: Line 48:
 
   0    LTM Latch on Pattern Match (in Bit Mode), or
 
   0    LTM Latch on Pattern Match (in Bit Mode), or
 
   0    DTE Deskew Timer Enable (in Handshake Modes)
 
   0    DTE Deskew Timer Enable (in Handshake Modes)
 +
 +
----
  
 
* Control Register 21h - Port A Handshake Specification Register (R/W)
 
* Control Register 21h - Port A Handshake Specification Register (R/W)
Line 49: Line 57:
 
                         4=Special Req, 5=Input Request, 7=Output Request)
 
                         4=Special Req, 5=Input Request, 7=Output Request)
 
   2-0    Deskew Time (MSBs of Deskew Timer Time Constant, LSB is forced 1)
 
   2-0    Deskew Time (MSBs of Deskew Timer Time Constant, LSB is forced 1)
 +
 +
----
  
 
* Control Register 08h - Port A Command and Status Register (Parts R/W)
 
* Control Register 08h - Port A Command and Status Register (Parts R/W)
Line 60: Line 70:
 
   5  IP  Interrupt Pending      (Read Only)
 
   5  IP  Interrupt Pending      (Read Only)
 
   4  ERR Interrupt Error        (Read Only)
 
   4  ERR Interrupt Error        (Read Only)
 
+
For Port A/B Registers:
* For Port A/B Registers:
+
 
   3  ORE Output Register Empty  (Read Only)
 
   3  ORE Output Register Empty  (Read Only)
 
   2  IRF Input Register Full    (Read Only)
 
   2  IRF Input Register Full    (Read Only)
 
   1  PMF Pattern Match Flag      (Read Only)
 
   1  PMF Pattern Match Flag      (Read Only)
 
   0  IOE Interrupt on Error
 
   0  IOE Interrupt on Error
 
+
For Counter/Timer Registers:
* For Counter/Timer Registers:
+
 
   3  RCC Read Counter Control    (Read/Set Only - cleared by reading CCR LSB)
 
   3  RCC Read Counter Control    (Read/Set Only - cleared by reading CCR LSB)
 
   2  GCB Gate Command Bit
 
   2  GCB Gate Command Bit
 
   1  TCB Trigger Command Bit    (Write Only) (Read returns 0)
 
   1  TCB Trigger Command Bit    (Write Only) (Read returns 0)
 
   0  CIP Counter in Progress    (Read Only)
 
   0  CIP Counter in Progress    (Read Only)
 
+
Set/Clear Command List:
* Set/Clear Command List:
+
 
   0=Null Code,  1=Clear IP & IUS
 
   0=Null Code,  1=Clear IP & IUS
 
   2=Set IUS,    3=Clear IUS
 
   2=Set IUS,    3=Clear IUS
 
   4=Set IP,    5=Clear IP
 
   4=Set IP,    5=Clear IP
 
   6=Set IE,    7=Clear IE
 
   6=Set IE,    7=Clear IE
 +
 +
----
  
 
* Control Register 22h - Data Path Polarity Register Port A (R/W)
 
* Control Register 22h - Data Path Polarity Register Port A (R/W)
Line 83: Line 92:
 
* Control Register 05h - Data Path Polarity Register Port C (4 LSBs only) (R/W)
 
* Control Register 05h - Data Path Polarity Register Port C (4 LSBs only) (R/W)
 
   7-0 DPP Data Path Polarity bits (0=Non-inverting, 1=Inverting)
 
   7-0 DPP Data Path Polarity bits (0=Non-inverting, 1=Inverting)
 +
 +
----
  
 
* Control Register 23h - Data Direction Register Port A (R/W)
 
* Control Register 23h - Data Direction Register Port A (R/W)
Line 88: Line 99:
 
* Control Register 06h - Data Direction Register Port C (4 LSBs only) (R/W)
 
* Control Register 06h - Data Direction Register Port C (4 LSBs only) (R/W)
 
   7-0 DD  Data Direction bits (0=Output Bit, 1=Input Bit)
 
   7-0 DD  Data Direction bits (0=Output Bit, 1=Input Bit)
 +
 +
----
  
 
* Control Register 24h - Special I/O Control Register Port A (R/W)
 
* Control Register 24h - Special I/O Control Register Port A (R/W)
Line 94: Line 107:
 
   7-0 SIO Special Input/Output bits (0=Normal Input or Output,
 
   7-0 SIO Special Input/Output bits (0=Normal Input or Output,
 
           1=Output with open drain, or Input with 1's catcher)
 
           1=Output with open drain, or Input with 1's catcher)
 +
 +
----
  
 
* Control Register 0Dh - Port Data Register Port A (R/W) (directly addressable)
 
* Control Register 0Dh - Port Data Register Port A (R/W) (directly addressable)
 
* Control Register 0Eh - Port Data Register Port B (R/W) (directly addressable)
 
* Control Register 0Eh - Port Data Register Port B (R/W) (directly addressable)
 
   7-0    Data Bits7-0 (usually 0=Low, 1=High, unless Polarity is inverted)
 
   7-0    Data Bits7-0 (usually 0=Low, 1=High, unless Polarity is inverted)
 +
 +
----
  
 
* Control Register 0Fh - Port Data Register Port C (R/W) (directly addressable)
 
* Control Register 0Fh - Port Data Register Port C (R/W) (directly addressable)
 
   7-4    Lock Bits3-0 (0=Writing Enabled, 1=Writing Inhibited)(Read returns 1)
 
   7-4    Lock Bits3-0 (0=Writing Enabled, 1=Writing Inhibited)(Read returns 1)
 
   3-0    Data Bits3-0 (usually 0=Low, 1=High, unless Polarity is inverted)
 
   3-0    Data Bits3-0 (usually 0=Low, 1=High, unless Polarity is inverted)
 +
 +
----
  
 
* Control Register 25h - Port A Pattern Polarity (PP) Register (R/W)
 
* Control Register 25h - Port A Pattern Polarity (PP) Register (R/W)
Line 118: Line 137:
 
   1  1  0  One-to-Zero Transition (falling edge)
 
   1  1  0  One-to-Zero Transition (falling edge)
 
   1  1  1  Zero-to-One Transition (raising edge)
 
   1  1  1  Zero-to-One Transition (raising edge)
 +
 +
----
  
 
* Control Register 1Ch - Counter/Timer 1 Mode Specification (R/W)
 
* Control Register 1Ch - Counter/Timer 1 Mode Specification (R/W)
Line 129: Line 150:
 
   2  REB  Retrigger Enable
 
   2  REB  Retrigger Enable
 
   1-0 DCS  Output Duty Cycle Select (0=Pulse,1=OneShot,2=SquareWave,3=Reserved)
 
   1-0 DCS  Output Duty Cycle Select (0=Pulse,1=OneShot,2=SquareWave,3=Reserved)
 +
 +
----
  
 
* Control Register 10h - Counter/Timer 1 Current Count Register MSB (R)
 
* Control Register 10h - Counter/Timer 1 Current Count Register MSB (R)
Line 137: Line 160:
 
* Control Register 15h - Counter/Timer 3 Current Count Register LSB (R)
 
* Control Register 15h - Counter/Timer 3 Current Count Register LSB (R)
 
   7-0 CCR Current Count Register (Read Only) (8bits of 16bit total)
 
   7-0 CCR Current Count Register (Read Only) (8bits of 16bit total)
 +
 +
----
  
 
* Control Register 16h - Counter/Timer 1 Time Constant Register MSB (R/W)
 
* Control Register 16h - Counter/Timer 1 Time Constant Register MSB (R/W)
Line 145: Line 170:
 
* Control Register 1Bh - Counter/Timer 3 Time Constant Register LSB (R/W)
 
* Control Register 1Bh - Counter/Timer 3 Time Constant Register LSB (R/W)
 
   7-0 TCR Time Constant Register (aka Reload value) (8bits of 16bit total)
 
   7-0 TCR Time Constant Register (aka Reload value) (8bits of 16bit total)
 +
 +
----
  
 
* '''Control Register 02h - Interrupt Vector Register Port A (R/W)'''
 
* '''Control Register 02h - Interrupt Vector Register Port A (R/W)'''
Line 152: Line 179:
 
Port A/B: In Priority Encoded Vector Mode:
 
Port A/B: In Priority Encoded Vector Mode:
 
   3-1    Number of highest Priority Bit with a match
 
   3-1    Number of highest Priority Bit with a match
 +
 +
----
  
 
* '''Port A/B: In all other Modes:'''
 
* '''Port A/B: In all other Modes:'''
Line 158: Line 187:
 
   3      Not auto-modified
 
   3      Not auto-modified
 
   2-1    Counter/Timer Number (0=C/T3, 1=C/T2, 2=C/T1, 3=Error)
 
   2-1    Counter/Timer Number (0=C/T3, 1=C/T2, 2=C/T1, 3=Error)
 +
 +
----
  
 
* '''Control Register 1Fh - Current Vector Register (R)'''
 
* '''Control Register 1Fh - Current Vector Register (R)'''
 
   7-0  Interrupt Vector Based on highest priority unmasked IP (IP=int pending)
 
   7-0  Interrupt Vector Based on highest priority unmasked IP (IP=int pending)
 
         If no interrupt pending then all 1's are output (ie. register is FFh)
 
         If no interrupt pending then all 1's are output (ie. register is FFh)

Revision as of 13:31, 29 January 2010

CIO Registers

  • Control Register 00h - Master Interrupt Control Register (R/W)
 7   MIE    Master Interrupt Enable
 6   DLC    Disable Lower Chain
 5   NV     No Vector
 4   PAVIS  Port A Vector Includes Status
 3   PBVIS  Port B Vector Includes Status
 2   CTVIS  Counter/Timers Vector Includes Status
 1          Right Justifies Addresses
             0=Shift Left (A0 from AD1)
             1=Right Justify (A0 from AD0)
 0          Reset (Caution: If set, requires a 3rd write to resurrect)

  • Control Register 01h - Master Configuration Control Register (R/W)
 7   PBE      Port B Enable
 6   CT1E     Counter/Timer 1 Enable
 5   CT2E     Counter/Timer 2 Enable
 4   PCE/CT3E Port C and Counter/Timer 3 Enable
 3   PLC      Port A-and-B Link Control (0=operate independently, 1=linked)
 2   PAE      Port A Enable
 0-1 LC       Counter/Timer Link Controls (see below)

  • Counter/Timer Link Controls values are:
 0=Counter/Timers are Independent
 1=Counter/Timer 1's /OUTPUT does Gate Counter/Timer 2
 2=Counter/Timer 1's /OUTPUT does Trigger Counter/Timer 2
 3=Counter/Timer 1's /OUTPUT is Counter/Timer 2's Count Input

  • Control Register 20h - Port A Mode Specification Register (R/W)
  • Control Register 28h - Port B Mode Specification Register (R/W)
 7-6  PTS Port Type Select (0=Bit Port, 1=Input, 2=Output, 3=Bidirectional)
 5    ITB Interrupt on Two Bytes
 4    SB  Single Buffered Mode
 3    IMO Interrupt on Match Only
 2-1  PMS Pattern Mode Specification (0=None, 1=AND, 2=OR, 3=OR-Priority)
 0    LTM Latch on Pattern Match (in Bit Mode), or
 0    DTE Deskew Timer Enable (in Handshake Modes)

  • Control Register 21h - Port A Handshake Specification Register (R/W)
  • Control Register 29h - Port B Handshake Specification Register (R/W)
 7-6 HTS Handshake Type (0=Interlocked, 1=Strobed, 2=Pulsed, 3=Three-Wire)
 5-3 RWS Request/Wait (0=Request/WAIT Disabled, 1=Output /WAIT, 3=Input /WAIT,
                       4=Special Req, 5=Input Request, 7=Output Request)
 2-0     Deskew Time (MSBs of Deskew Timer Time Constant, LSB is forced 1)

  • Control Register 08h - Port A Command and Status Register (Parts R/W)
  • Control Register 09h - Port B Command and Status Register (Parts R/W)
  • Control Register 0Ah - Counter/Timer 1 Command and Status (Parts R/W)
  • Control Register 0Bh - Counter/Timer 2 Command and Status (Parts R/W)
  • Control Register 0Ch - Counter/Timer 3 Command and Status (Parts R/W)
 7-5     Set/Clear Command       (Write Only) (see command list)
 7   IUS Interrupt Under Service (Read Only)
 6   IE  Interrupt Enable        (Read Only)
 5   IP  Interrupt Pending       (Read Only)
 4   ERR Interrupt Error         (Read Only)

For Port A/B Registers:

 3   ORE Output Register Empty   (Read Only)
 2   IRF Input Register Full     (Read Only)
 1   PMF Pattern Match Flag      (Read Only)
 0   IOE Interrupt on Error

For Counter/Timer Registers:

 3   RCC Read Counter Control    (Read/Set Only - cleared by reading CCR LSB)
 2   GCB Gate Command Bit
 1   TCB Trigger Command Bit     (Write Only) (Read returns 0)
 0   CIP Counter in Progress     (Read Only)

Set/Clear Command List:

 0=Null Code,  1=Clear IP & IUS
 2=Set IUS,    3=Clear IUS
 4=Set IP,     5=Clear IP
 6=Set IE,     7=Clear IE

  • Control Register 22h - Data Path Polarity Register Port A (R/W)
  • Control Register 2Ah - Data Path Polarity Register Port B (R/W)
  • Control Register 05h - Data Path Polarity Register Port C (4 LSBs only) (R/W)
 7-0 DPP Data Path Polarity bits (0=Non-inverting, 1=Inverting)

  • Control Register 23h - Data Direction Register Port A (R/W)
  • Control Register 2Bh - Data Direction Register Port B (R/W)
  • Control Register 06h - Data Direction Register Port C (4 LSBs only) (R/W)
 7-0 DD  Data Direction bits (0=Output Bit, 1=Input Bit)

  • Control Register 24h - Special I/O Control Register Port A (R/W)
  • Control Register 2Ch - Special I/O Control Register Port B (R/W)
  • Control Register 07h - Special I/O Control Register Port C (4 LSBs only)(R/W)
 7-0 SIO Special Input/Output bits (0=Normal Input or Output,
         1=Output with open drain, or Input with 1's catcher)

  • Control Register 0Dh - Port Data Register Port A (R/W) (directly addressable)
  • Control Register 0Eh - Port Data Register Port B (R/W) (directly addressable)
 7-0     Data Bits7-0 (usually 0=Low, 1=High, unless Polarity is inverted)

  • Control Register 0Fh - Port Data Register Port C (R/W) (directly addressable)
 7-4     Lock Bits3-0 (0=Writing Enabled, 1=Writing Inhibited)(Read returns 1)
 3-0     Data Bits3-0 (usually 0=Low, 1=High, unless Polarity is inverted)

  • Control Register 25h - Port A Pattern Polarity (PP) Register (R/W)
  • Control Register 26h - Port A Pattern Transition (PT) Register (R/W)
  • Control Register 27h - Port A Pattern Mask (PM) Register (R/W)
  • Control Register 2Dh - Port B Pattern Polarity (PP) Register (R/W)
  • Control Register 2Eh - Port B Pattern Transition (PT) Register (R/W)
  • Control Register 2Fh - Port B Pattern Mask (PM) Register (R/W)
 7-0  Pattern Bits (PP/PT/PM for Pattern Polarity/Transition/Mask accordingly)

Possible combinations of the PP/PT/PM Bits are:

 PM PT PP Pattern Specification
 0  0  x  Bit Masked Off
 0  1  x  Any Transition
 1  0  0  Zero
 1  0  1  One
 1  1  0  One-to-Zero Transition (falling edge)
 1  1  1  Zero-to-One Transition (raising edge)

  • Control Register 1Ch - Counter/Timer 1 Mode Specification (R/W)
  • Control Register 1Dh - Counter/Timer 2 Mode Specification (R/W)
  • Control Register 1Eh - Counter/Timer 3 Mode Specification (R/W)
 7   C/SC Continuous/Single Cycle (0=Singe Cycle, 1=Continuous)
 6   EOE  External Output Enable
 5   ECE  External Count Enable
 4   ETE  External Trigger Enable
 3   EGE  External Gate Enable
 2   REB  Retrigger Enable
 1-0 DCS  Output Duty Cycle Select (0=Pulse,1=OneShot,2=SquareWave,3=Reserved)

  • Control Register 10h - Counter/Timer 1 Current Count Register MSB (R)
  • Control Register 11h - Counter/Timer 1 Current Count Register LSB (R)
  • Control Register 12h - Counter/Timer 2 Current Count Register MSB (R)
  • Control Register 13h - Counter/Timer 2 Current Count Register LSB (R)
  • Control Register 14h - Counter/Timer 3 Current Count Register MSB (R)
  • Control Register 15h - Counter/Timer 3 Current Count Register LSB (R)
 7-0 CCR Current Count Register (Read Only) (8bits of 16bit total)

  • Control Register 16h - Counter/Timer 1 Time Constant Register MSB (R/W)
  • Control Register 17h - Counter/Timer 1 Time Constant Register LSB (R/W)
  • Control Register 18h - Counter/Timer 2 Time Constant Register MSB (R/W)
  • Control Register 19h - Counter/Timer 2 Time Constant Register LSB (R/W)
  • Control Register 1Ah - Counter/Timer 3 Time Constant Register MSB (R/W)
  • Control Register 1Bh - Counter/Timer 3 Time Constant Register LSB (R/W)
 7-0 TCR Time Constant Register (aka Reload value) (8bits of 16bit total)

  • Control Register 02h - Interrupt Vector Register Port A (R/W)
  • Control Register 03h - Interrupt Vector Register Port B (R/W)
  • Control Register 04h - Interrupt Vector Register Counter/Timers (R/W)
 7-0    Interrupt Vector (Bit3-1 may be automatically modified, see below)

Port A/B: In Priority Encoded Vector Mode:

 3-1    Number of highest Priority Bit with a match

  • Port A/B: In all other Modes:
 3-1    Bit3-1=All zero if Error, or otherwise Bit3=ORE, Bit2=IRF, Bit1=PMF

Counter/Timer:

 3      Not auto-modified
 2-1    Counter/Timer Number (0=C/T3, 1=C/T2, 2=C/T1, 3=Error)

  • Control Register 1Fh - Current Vector Register (R)
 7-0   Interrupt Vector Based on highest priority unmasked IP (IP=int pending)
       If no interrupt pending then all 1's are output (ie. register is FFh)