VME-PPG32

VME-PPG32 - pulse pattern generator VME FPGA board

References

• [1] VME-PPG32 Rev0 (REA 198) project page on edev.triumf.ca
• [2] VME-PPG32 Rev1 (REA 198) project page on edev.triumf.ca
• [3] Rev0 board schematics
• [4] Rev1 board schematics
• [5] Svn repository for VME-PPG32-Rev0 initial test firmware (IO32 function only, no PPG function)
• [6] Current PPG firmware Source/binary

General characteristics

Available hardware

• Altera cyclone 3 FPGA: EP3C40Q240C8
• Serial flash for FPGA configuration: Altera EPCS16
• VME interface: VME-D[31..0] bidirectional, VME-A[23..0] input only, DTACK output, no BERR, no RETRY/RESP. VME-A[31..20] input only connected only to address decoder FPGA (Altera MAX-something CPLD). This permits all single-word transfer modes, 32-bit DMA (BLT32) and 2eVME DMA (only drives D-lines, but still faster than BLT32). 64-bit DMA (MBLT64) and 2eSST are impossible.
• 32 NIM outputs
• 4 NIM inputs
• 32 "NIM output" LEDs
• 4 "NIM input" LEDs
• 1 "VME access" LED
• 2 output serial DAC: AD5439YRUZ

PPG characteristics

  4k words (128bit words) of program memory.
  256 entry stack.
  Halt/Continue/Loop/Subroutine/Branch instructions
  100Mhz clock (derived from either 50Mhz internal crystal or external 20Mhz clock input)
  fixed 3 clk per instruction plus 32bit delay individualy programmable for each instruction

  FPGA resource Usage : 1044 LE, 500 kbits Memory

VME interface

VME A32/D32 access only. Rotary switches SW1, SW2 and SW3 set the upper 12 bits of the address. VME registers are listed in the table below.

Registers

Number	Address	Name	Access	Description
0	0x00000	CSR	RW	Control/Status Register
1	0x00004	Test	RW	Test Register
2	0x00008	Addr	RW	Program Address Register
3	0x0000C	Inst_Lo	RW	Instruction Register Part 1/4
4	0x00010	Inst_Med	RW	Instruction Register Part 2/4
5	0x00014	Inst_Hi	RW	Instruction Register Part 3/4
6	0x00018	Inst_Top	RW	Instruction Register Part 4/4
7	0x0001C	Inv_Mask	RW	Output Inversion Mask
8	0x00020	Version	R	Firmware Version Register
9	0x00024	Flash	RW	Serial Flash Control Register
10	0x00028	Serial	R	Serial Number Register
11	0x0002C	Hardware	R	hardware Identification Register

Test Register (0x00000)

Simple Test Register - Value Written is preserved and can be read back.

CSR Register (0x00004)

The first 5 bits control the ppg, the remaining 26 bits provide read-only status information. (writes to the 26 bits of status information are ignored, and overwritten on the next status update)

CSR Description

Bit	Name	Access	description
0	Run	R/W	Run Control/Status
1	Ext-Clk	R/W	The PPG logic uses the external Clk
2	Ext-Start	R/W
3	Slow-Clk	R/W
4	Test-Mode	R/W
5-31	Status	R	Readback of PC,SP,Current Delay Counter

RUN bit: Writing 1 here instructs the ppg to begin executing its program, reading this bit returns 1 if the program is still running, or 0 if halted.

Ext_Clk bit: Writing 1 here switches the ppg logic to use the external CLK (Nim_Input[0]) (The VME interface always uses the internal clock)

Ext_Start bit: Writing 1 here disables the CSR-Run-bit-start (Reading this bit still returns the correct status), and switches control to the External Start input (NIM_INPUT[1])

Slow-Clk bit: Writing 1 here Switches the ppg clock to a much slower one (2kHz) for low speed/long delay operation. NOTE - this is currently ignored.

Test-mode bit: Writing 1 here Changes the outputs (LED/NIM) to simple follow the state of the Address register.

Address Register (0x00008)

Sets PPG Program Memory Address - next instruction will be written to this location. Also when program is started, execution begins from this address. Also in test-Mode, the NIM/LED outputs follow the state of this register.

Instruction Registers (0x0000C - 0x00018)

Registers to hold the 128bit Program Instructions. Writing the Upper register triggers the storing of the entire 128bit instruction to the address currently in the address register.

The instructions format is as follows ...

Instruction Format

Bits 0-31	Bits 32-63	Bits 64-95	Bits 96-115	Bits 116-117	Bits 118-127
32 Output Set Bits	32 Output Clear Bits	32bit Delay Count	20bit Data	4bit instruction type	Ignored

The 32bit delay count at 100Mhz gives maximum delay of 10 seconds per instruction.

  The instruction types are ...
  0 - Halt
  1 - Continue
  2 - new Loop        ( 20 bit data used for count - i.e. maximum 1 million )
  3 - End Loop
  4 - Call Subroutine ( 20 bit data used for address )
  5 - Return from subroutine
  6 - Branch          ( 20 bit data used for address )

Output Inversion Mask (0x0001C)

32 individual inversion bits (1 per output) a 1 inverts the state of that output.

Firmware Version (0x00020)

Returns the 32bit unix timestamp corresponding to the date this firmware was compiled.

Serial Flash Control (0x00024)

Used for reading/Writing to the Configuration Flash device (Reading/Updating firmware)

Serial Number (0x00028)

Returns the module serial number, and Board revision (if set) or -1

hardware Type (0x0002C)

Returns a 32 bit description of this hardware - which should confirm the identity of this module as a vme-ppg32

Front Panel

NIM Inputs

  The Input assignments are (Left-Right, Top-Bottom) ...
  0 - External Clock (20Mhz, internally scaled - 100Mhz)
  1 - External Start (Not fully tested yet) Needs to stay high (low => stop!)
  2 - Unassigned
  3 - Unassigned

Input LEDs

  The Input LED assignments are (Left-Right, Top-Bottom) ...
  0 - External Clock Good indicator (Lit => Clock is good)
  1 - Program Running
  2 - Clock setting (Lit => External Clk)
  3 - NimIn[3] status

Test Software

c-shell script to run 2 nested loops

  set dec_hex=( 0x0  0x1  0x2  0x3  0x4  0x5  0x6  0x7  \
                0x8  0x9  0xa  0xb  0xc  0xd  0xe  0xf  \
                0x10 0x11 0x12 0x13 0x14 0x15 0x16 0x17 \
                0x18 0x19 0x1a 0x1b 0x1c 0x1d 0x1e 0x1f \
                0x20 0x21 0x22 0x23 0x24 0x25 0x26 0x27 )
  
  # dly4,loop4,dly3,loop6,dly2,end,end
  set inst=(                                                \
     0xff  0x00  0x4  0x100000   0x0   0x0   0x0  0x200004  \
     0x1   0x1   0x3  0x100000   0x0   0x0   0x0  0x200006  \
     0x2   0x2   0x2  0x100000   0x0   0x0   0x0  0x300000  \
     0x0   0x0   0x0  0x300000   0x0   0x0   0x0  0x000000  )
  
  set i=0
  set j=0
  while( $i < $#inst )
     @ j++; vme_poke -a VME_A32UD -A 0x00100008 -d VME_D32 $dec_hex[$j]
     @ i++; vme_poke -a VME_A32UD -A 0x0010000c -d VME_D32 $inst[$i]
     @ i++; vme_poke -a VME_A32UD -A 0x00100010 -d VME_D32 $inst[$i]
     @ i++; vme_poke -a VME_A32UD -A 0x00100014 -d VME_D32 $inst[$i]
     @ i++; vme_poke -a VME_A32UD -A 0x00100018 -d VME_D32 $inst[$i]
  end
  
  # start program (from addr 0)...
  vme_poke -a VME_A32UD -A 0x00100008 -d VME_D32 0x0
  vme_poke -a VME_A32UD -A 0x00100000 -d VME_D32 0x1