An Example of What Happens When the Number of Keyboard Keys Goes UP
And the Number of Shifts Goes DOWN: The HP67 versus the HP97
HP 67 HP 97
tot # keys 35 56
# generic shift keys (i.e. "f", "g") 3 1
f, g, h f
# marked generically-shifted fcns (f ASIN, etc.) 75 52
   
# unmarked generically-shifted fcns (f ASIN) 0 0
# functional shift keys (i.e. "DSP", "STO") 4 6
STO, RCL, DSP, GTO LBL, GTO, GSB, STO, RCL, DSP
# unmarked shifted fcns (DSP n, etc.) 59 92
# 3-key shifted A 3 1
SF, CF, F? 0-3 DSZ (i), ISZ (i)
# fcns per 3-key shifted A 4 2
# 3-key sequences B 1 3
GTO f a-e LBL f, GTO f, GSB f
# fcns per 3-key seq B 5 5
# 3-key sequences C 1 3
f LBL 0-9 A-E, g LBLf a-e f STF, f CLF, f F?
# fcns per 3-key seq C 20 4
 
# 3-key sequences D 4 4
STO + - x 0-9, (i) STO +, STO -, STO x, STO
# fcns per 3-key seq D 11 11
 
# 3-key sequences E 1
f GSB 0-9,A-E,(i), g GSBf a-e
# fcns per 3-key seq E 21
                               
 
# primary keys 32 55 tot # keys - tot # shift keys
tot # primary fcns 27 47 # primary keys - # functional shift keys
tot # shift keys 7 7 # generic shift keys + # functional shift keys
tot # 2-key shifted fcns 134 144 # marked shifted fcns + # unmarked shifted fcns
tot # 3-key sequences 102 73 (# 3-key sequences A * # fcns per 3-key seq A) + (# 3-key sequences B * # fcns per 3-key seq B)++( E)
tot # functions 263 264 # primary keys + tot # 2-key shifted functions + tot # 3-key sequences (Only the non-programmable PRINT PRGM added to HP97)
Keyboard Clutter (# fcns per key) 3.257 1.964 tot # fcns on keyboard / tot # keys
Keystroke Count 601 554 # primary keys + (2 * tot # shifted functions) + (3 * tot # 3-key sequences)
Keystroke count per function 2.285 2.098 Keystroke count / total # functions
Ref: 65 Notes V4N1P8
 

 

 
                                                          Detailed HP67 Keyboard Metrics                                   Detailed HP97 Keyboard Metrics