TITLE 'FILE: Peel12.psf' DESIGNER 'Dr. Marcus O. Durham' DATE '27 October 2004' DESCRIPTION The description is optional. The title block information must be enclosed within single quotation marks. The device must be specified. END_DESC; PEEL22CV10 " ___ ____ " | \/ | " CLK { 1 24 } Vcc " I1 { 2 23 } F9 " I2 { 3 22 } F8 " I3 { 4 21 } F7 " I4 { 5 20 } F6 " I5 { 6 19 } F5 " I6 { 7 18 } F4 " I7 { 8 17 } F3 " I8 { 9 16 } F2 " I9 { 10 15 } F1 " I10 { 11 14 } F0 " Gnd { 12 13 } I11 " |_________| "Pins "Registered clock or input: 1 "Input: 2,3,4,5,6,7,8,9,10,11, 13 "Input or output logic macro cell (OLMC): " 14,15,16,17,18,19,20,21,22,23 " "------- "Symbols are used for programming functions " Quote = comments not printed " ' = comments for header to be printed' " ! = not " & = AND " # = OR " $ = exclusive-or " = is equation for combination logic " ; = last character in an equation "------- "Application "Memory can be changed from EPROM to SRAM "by changing the chip & /OE jumper. "PLD / PEEL program selects MemP1 and MemP27. "EPROM: MemP1=Vpp, MemP27=A14 requires /OE=/PSEN jumper "SRAM: MemP1=A14, MemP27=/WE, requires /OE=/RD or Ground jumper "MMIO: uses A15 "SRAM: !A15 "CHECK MemP27: IT CAN GO LOW IF !PSENn, IE RDn ACTIVATES A14 "------- "Address assignments. "Because of the Don't Cares, the effective "memory-mapped address can be 8xxn. "Memory-mapped read or write is address A15 only. "8000h "Keypad latches are read row & write column "8001h "DisLE latch is high. "8002h " "Isp OE is select low on invert reset input. "------- "Memory switching latch was for old BIOS "Kept for record purposes, original file is lost. "CE = WRFF & ucA7 & ucD0 # !WRFF&CE "OE = PSEN&RD # RD&!CE "--------------- "PIN ASSIGNMENTS "INPUTS A00 pin 2 A01 pin 3 A02 pin 4 A14 pin 5 A15 pin 6 AD00 pin 7 Reset pin 8 PSEN pin 9 Wrn pin 10 Rdn pin 11 " pin 13 "INPUT / OUTPUT CELLS "The input/output cells require specification. "The format is "IOC (pin-number 'name' polarity logic feedback) "Polarity can be pos(itive) or neg(ative). "Logic can be com(binational) or reg(ister) "Feedback can be from the feed_pin or feed_reg. IOC (14 'MmRd' POS COM FEED_PIN) IOC (15 'MmWr' POS COM FEED_PIN) IOC (16 'DisLe' POS COM FEED_PIN) IOC (18 'KeyOEn' POS COM FEED_PIN) IOC (19 'KeyLE' POS COM FEED_PIN) IOC (20 'ISPOEn' POS COM FEED_PIN) IOC (21 'MemP27' POS COM FEED_PIN) IOC (22 'Oen' POS COM FEED_PIN) IOC (23 'MemP1' POS COM FEED_PIN) DEFINE "Define variables do not have feedback. MmAd = A15 EQUATIONS "Equations define logic functions "Register variables have .D extension for D FF. "Combinational variables have .COM extension. IspOEn.com = !Reset; MemP1.com = A14 & (!A15 & (!WRn #!RDn)); MemP27.com = (!PSEN & A14) # (WRn & !A15); Oen.com = PSEN # !(!RDn & !A15); MmWr.com = A15 & !WRn; MmRd.com = A15 & !RDn; KeyOEn.com = !(MmRd& !A02& !A01& A00); KeyLE.com = (MmWr& !A02& !A01& A00); DisLE.com = (MmWr & !A02 & A01 & !A00); TEST_VECTORS "Test vectors are used to verify the logic works. "This is a partial truth table. "The first line specifies input output variables. "Next line are input output values. "C is clock transition. "0 is an input low, 1 is an input high "L is output low, H is output high. "X is don't care (A00 A15 A00 Wrn MmWr DisLE -> KeyOEn) C 0 X 0 L x X C 0 X 1 L x X C 1 X 0 H x X C 1 X 1 L x X