<-[[.:start]] ====== DM41X Progs ====== ==== Useful Memo prog ==== {{ :public:calculator:progs:03319.pdf | MEMO }} By Gary Goodman from HP document collection. Dated 24/3/85 ===== TI : calculate 65c22 Timer values for tone generation ===== ==== Counter calculation ==== The required count is calculated from ''Φ₂'' and the audio frequency required. Count (decimal) { Φ₂ / ( 2 x F ) } - 2 for 1000Hz and a 1MHz Φ₂ : Count = { 1,000,000 / ( 2 X 1000 ) } - 2 = 498 498d -> $01F2 Run as XEQALPHA''TI''ALPHA Prompt ''F'' for required audio tone frequency. Enter freq R/S Result is the 2-byte value for T1CL & T1CH e.g. XEQALPHA''TI''ALPHA 1000 R/S Result: $001F2 The Counter should be set to T1CH = $01 T1CL = $F2 Entered as follows (make sure you're in DECS mode in Ladybug while entering the program - otherwise the ''1000000'' won't be interpreted correctly). When viewing/editing the program later it will look different! LBL ¬TI DECS WSIZE 20 ¬ F PROMPT STI 01 1000000 ENTERI LDI 01 2 x / 2 - HEXS RTN ===== BFil ===== ++++ Butterworth HPF/LPF Filter designer | LBL ¬BFIL SF 00 ¬MHZ ? PROMPT 1 E6 * STO 11 ¬N PROMPT x<0? CF 00 STO 10 XEQ 06 LBL 01 RCL 12 INT XEQ 00 FS? 00 1/x STO IND 12 ISG 12 GTO 01 ¬COEFFICIENTS FIX 3 STOP ENG 3 XEQ 06 LBL 02 RCL 12 INT RCL IND 12 RCL 11 2 * PI * / STO IND 12 ISG 12 GTO 02 XEQ 06 LBL 03 RCL 12 INT 2 / FRC FS? 00 GTO 09 GTO 10 LBL 09 ¬HPF x=0? GTO 05 GTO 04 RTN LBL 10 ¬LPF x=0? GTO 04 GTO 05 RTN LBL 04 RCL IND 12 50 * STO IND 12 ISG 12 GTO 03 RTN LBL 05 RCL IND 12 50 / STO IND 12 ISG 12 GTO 03 RTN LBL 06 RCL 10 ABS 1000 / 1 + STO 12 RTN LBL 00 2 * 1 - 180 * RCL 10 ABS 2 * / SIN 2 * RTN END ++++ ==== Examples ==== === 5MHz 5-pole LPF === XEQALPHABFILALPHA MHZ ? 5 R/S N ''Order/poles = N'' ''Positive for HPF'' ''Negative for LPF'' ''5 pole LPF = -5'' 5CHSR/S COEFFICIENTS 0.618 (at this point you can RCL 01 etc. up to RCL 05 to see the calculated Butterworth Coefficients) * R01 : 0.618 * R02 : 1.618 * R03 : 2.000 * R04 : 1.618 * R05 : 0.618 R/S LPF 393.5 -12 The calculated component values are now in Reg 01 - Reg 05 * R01 : 393.5pf * R02 : 2.575uH * R03 : 1.273nF * R04 : 2.575uH * R05 : 393.5pF === 1MHz 7 pole HPF === XEQALPHABFILALPHA MHZ ? 1 R/S N ''Order/poles = N'' ''Positive for HPF'' ''Negative for LPF'' ''7 pole HPF = 7'' 7R/S COEFFICIENTS 2.247 (at this point you can RCL 01 etc. up to RCL 07 to see the calculated Butterworth Coefficients) * R01 : 2.247 * R02 : 0.802 * R03 : 0.555 * R04 : 0.500 * R05 : 0.555 * R06 : 0.802 * R07 : 2.247 R/S HPF 17.88 -06 The calculated component values are now in Reg 01 - Reg 07 * R01 : 17.88uH * R02 : 2.553nF * R03 : 4.416uH * R04 : 1.592nF * R05 : 4.416uH * R06 : 2.553nF * R07 : 17.88uH ===== Page Info ===== Page created Thu May 26 18:35:00 2022 by John Pumford-Green Page last updated: ~~LASTMOD~~ {{tag>dm41x calculator}} --- //John Pumford-Green 24/04/23 16:07// ===== Further Information ===== {{tag>}}