VersaLogic Python EBX-11 Reference Manual page 63

;Set PWMs to manual mode (required)
; PWM 1 Configuration Register = 5Ch
; PWM 2 Configuration Register = 5Dh
; PWM 3 Configuration Register = 5Eh
;
MOV DX, C70h
MOV AL, 5Ch
OUT DX, AL
MOV DX, C71h
IN AL, DX
OR AL, E0h
OUT DX, AL
;Set Zone X Low Temp Limits to valid values (Required)
;All three must be set even if only one PWM is used...
MOV DX, C70h
MOV AL, 67h
OUT DX, AL
MOV DX, C71h
MOV AL, 81h
OUT DX, AL
MOV DX, C70h
MOV AL, 68h
OUT DX, AL
MOV DX, C71h
MOV AL, 81h
OUT DX, AL
MOV DX, C70h
MOV AL, 69h
OUT DX, AL
MOV DX, C71h
MOV AL, 81h
OUT DX, AL
;Set PWM current duty cycle (optional)
; PWM 1 Current Duty Cycle Register = 30h
; PWM 2 Current Duty Cycle Register = 31h
; PWM 3 Current Duty Cycle Register = 32h
;
MOV DX, C70h
MOV AL, 30h
OUT DX, AL
MOV DX, C71h
MOV AL, 80h
OUT DX, AL
;Set PWM Frequency (optional)
; Zone 1 Range/PWM 1 Frequency Register = 5Fh
; Zone 2 Range/PWM 2 Frequency Register = 60h
; Zone 3 Range/PWM 3 Frequency Register = 61h
;
; Frequency = low nibble
; X0 = 11.0 Hz
; X1 = 14.6Hz
; X2 = 21.9Hz
; X3 = 29.3Hz
EBX-11 Reference manual
;PWM 1 Configuration Register
;Read Current Value
;Set Manual Mode
;Zone 1 Low Temp Limit Register
;any value other than default of 80h
;Zone 2 Low Temp Limit Register
;Any value other than default of 80h
;Zone 3 Low Temp Limit Register
;Any value other than default of 80h
;PWM 1 Current Duty Cycle Register
;50% Duty Cycle, 40h = 25%, etc.
X6 = 58.6Hz
X7 = 87.7Hz
X8 = 15 KHz
X9 = 20 KHz
Interfaces and Connectors
57