tcl/fpga/xilinx-xadc.cfg

   1 # Xilinx XADC support for 7 Series FPGAs
   2 #
   3 # The 7 Series FPGAs contain an on-chip 12 bit ADC that can probe die
   4 # temperature, internal power supply rail voltages as well as external
   5 # voltages. The XADC is available both from fabric as well as through the
   6 # JTAG TAP.
   7 #
   8 # This code implements access throught the JTAG TAP.
   9 #
  10 # https://www.xilinx.com/support/documentation/user_guides/ug480_7Series_XADC.pdf
  11
  12 # build a 32 bit DRP command for the XADC DR
  13 proc xadc_cmd {cmd addr data} {
  14         array set cmds {
  15                 NOP 0x00
  16                 READ 0x01
  17                 WRITE 0x02
  18         }
  19         return [expr ($cmds($cmd) << 26) | ($addr << 16) | ($data << 0)]
  20 }
  21
  22 # XADC register addresses
  23 # Some addresses (status registers 0-3) have special function when written to.
  24 proc XADC {key} {
  25         array set addrs {
  26                 TEMP 0x00
  27                 LOCK 0x00
  28                 VCCINT 0x01
  29                 VCCAUX 0x02
  30                 VAUXEN 0x02
  31                 VPVN 0x03
  32                 RESET 0x03
  33                 VREFP 0x04
  34                 VREFN 0x05
  35                 VCCBRAM 0x06
  36                 SUPAOFFS 0x08
  37                 ADCAOFFS 0x09
  38                 ADCAGAIN 0x0a
  39                 VCCPINT 0x0d
  40                 VCCPAUX 0x0e
  41                 VCCODDR 0x0f
  42                 VAUX0 0x10
  43                 VAUX1 0x11
  44                 VAUX2 0x12
  45                 VAUX3 0x13
  46                 VAUX4 0x14
  47                 VAUX5 0x15
  48                 VAUX6 0x16
  49                 VAUX7 0x17
  50                 VAUX8 0x18
  51                 VAUX9 0x19
  52                 VAUX10 0x1a
  53                 VAUX11 0x1b
  54                 VAUX12 0x1c
  55                 VAUX13 0x1d
  56                 VAUX14 0x1e
  57                 VAUX15 0x1f
  58                 SUPBOFFS 0x30
  59                 ADCBOFFS 0x31
  60                 ADCBGAIN 0x32
  61                 FLAG 0x3f
  62                 CFG0 0x40
  63                 CFG1 0x41
  64                 CFG2 0x42
  65                 SEQ0 0x48
  66                 SEQ1 0x49
  67                 SEQ2 0x4a
  68                 SEQ3 0x4b
  69                 SEQ4 0x4c
  70                 SEQ5 0x4d
  71                 SEQ6 0x4e
  72                 SEQ7 0x4f
  73                 ALARM0 0x50
  74                 ALARM1 0x51
  75                 ALARM2 0x52
  76                 ALARM3 0x53
  77                 ALARM4 0x54
  78                 ALARM5 0x55
  79                 ALARM6 0x56
  80                 ALARM7 0x57
  81                 ALARM8 0x58
  82                 ALARM9 0x59
  83                 ALARM10 0x5a
  84                 ALARM11 0x5b
  85                 ALARM12 0x5c
  86                 ALARM13 0x5d
  87                 ALARM14 0x5e
  88                 ALARM15 0x5f
  89         }
  90         return $addrs($key)
  91 }
  92
  93 # Select the XADC DR
  94 proc xadc_select {tap} {
  95         set XADC_IR 0x37
  96         irscan $tap $XADC_IR
  97         runtest 10
  98 }
  99
 100 # XADC transfer
 101 proc xadc_xfer {tap cmd addr data} {
 102         set ret [drscan $tap 32 [xadc_cmd $cmd $addr $data]]
 103         runtest 10
 104         return [expr 0x$ret]
 105 }
 106
 107 # XADC register write
 108 proc xadc_write {tap addr data} {
 109         xadc_xfer $tap WRITE $addr $data
 110 }
 111
 112 # XADC register read, non-pipelined
 113 proc xadc_read {tap addr} {
 114         xadc_xfer $tap READ $addr 0
 115         return [xadc_xfer $tap NOP 0 0]
 116 }
 117
 118 # convert 16 bit register code from ADC measurement on
 119 # external voltages (VAUX) to Volt
 120 proc xadc_volt {code} {
 121         return [expr $code * 1./(1 << 16)]
 122 }
 123
 124 # convert 16 bit temperature measurement to Celsius
 125 proc xadc_temp {code} {
 126         return [expr $code * 503.975/(1 << 16) - 273.15]
 127 }
 128
 129 # convert 16 bit suppply voltage measurement to Volt
 130 proc xadc_sup {code} {
 131         return [expr $code * 3./(1 << 16)]
 132 }
 133
 134 # perform a single channel measurement using default settings
 135 proc xadc_single {tap ch} {
 136         set cfg0 [xadc_read $tap [XADC CFG0]]
 137         set cfg1 [xadc_read $tap [XADC CFG1]]
 138         # set channel
 139         xadc_write $tap [XADC CFG0] $cfg0
 140         # single channel, disable the sequencer
 141         xadc_write $tap [XADC CFG1] 0x3000
 142         # leave some time for the conversion
 143         runtest 100
 144         set ret [xadc_read $tap [XADC $ch]]
 145         # restore CFG0/1
 146         xadc_write $tap [XADC CFG0] $cfg0
 147         xadc_write $tap [XADC CFG1] $cfg1
 148         return $ret
 149 }
 150
 151 # measure all internal voltages
 152 proc xadc_report {tap} {
 153         xadc_select $tap
 154         echo "TEMP [format %.2f [xadc_temp [xadc_single $tap TEMP]]] C"
 155         foreach ch [list VCCINT VCCAUX VCCBRAM VPVN VREFP VREFN \
 156                 VCCPINT VCCPAUX VCCODDR] {
 157                 echo "$ch [format %.3f [xadc_sup [xadc_single $tap $ch]]] V"
 158         }
 159 }