jlahti@csc.fi (03/12/91)
I happen to have an old AST SixPakPlus card, and a joystick. My son wants to use that joystick, but AST card needs two chips, "16-pin IC (No. 558CP) and a 20-pin IC (No. 74LS244)" according the manual. I found the last one, but in those electronic stores I tried, they could not help me with 558CP, because the manufacturer was not mentioned. I even phoned to local AST representative, but they were no better. So: can anyone tell or guess, what does 558CP do and who has done it... Yes, I know: it had been easier to byu totally new joystic adapter card...
lamb@brahms.udel.edu (Richard E Lamb) (03/12/91)
The 558 is a quad timer (4 - 555 timers in a single chip). I seem to recall seeing them on the blue wall at Radio Snack... worth a try!
squishy@casbah.acns.nwu.edu (Shishin Yamada) (03/12/91)
In article <1991Mar11.223053.1@csc.fi> jlahti@csc.fi writes: >I happen to have an old AST SixPakPlus card, and a joystick. >My son wants to use that joystick, but AST card needs two chips, >"16-pin IC (No. 558CP) and a 20-pin IC (No. 74LS244)" according >the manual. >I found the last one, but in those electronic stores I tried, >they could not help me with 558CP, because the manufacturer >was not mentioned. I even phoned to local AST representative, >but they were no better. So: can anyone tell or guess, what >does 558CP do and who has done it... >Yes, I know: it had been easier to byu totally new joystic adapter >card... The 558CP is the Quad version of the ever-popular 555 timer. Also the 74LS244 stands for the folloring: 74 = TTL Familly of Logic Chips LS = Low Power Schottkey Type Logic Familly. 244 = Octal Buffer (Non-Inverting). The 558CP and 74LS244 are VERY common parts for any good electronics parts store. Even Radio Shack should carry these. Popular manufacturers of the 588 are Texas Instruments and Motorola. Both chips should not cost more than $2 (OK, ridiculous price at Radio Shark). The 558 is probably used as with a potentiometer in the joystick as an oscillator. The oscillator is then used to 'count' the position of the joystick by the oscillators frequency. (I dunno for sure, as I am a Mac Man. It may even be set up as a one-shot, like the old Apple II). The 74LS244 is used to interface onto the bus line. It has two enable lines that connect to eight tri-state buffers. This allows the joystick data to be written onto the bus only when enabled. A better question might be, why did these chips fry themselves, and you should consider that before just plugging in the replacements. ===================================================== Shishin "Squish" Yamada |\/\/\/| squishy@casbah.acns.nwu.edu /---------\ | | Northwestern University | Yo | (o)(o) | Electrical Engineering | Dudes! \ ( < ) Class of 1991 \__________\ |___/ | \ | "Life sucks, but Death swallows!" / \ /______\ =====================================================
ray@ole.UUCP (Ray Berry) (03/13/91)
jlahti@csc.fi writes: >but they were no better. So: can anyone tell or guess, what >does 558CP do and who has done it... It's a quad monostable timer chip. Signetics is the (primary) source. You might also find an Exar version. -- Ray Berry kb7ht uucp: ...sumax!ole!ray CIS: 73407,3152 /* "inquire within" */
ee8kh@gdt.bath.ac.uk (K House) (03/15/91)
ray@ole.UUCP (Ray Berry) writes: >jlahti@csc.fi writes: >>but they were no better. So: can anyone tell or guess, what >>does 558CP do and who has done it... > It's a quad monostable timer chip. Signetics is the (primary) >source. You might also find an Exar version. >-- >Ray Berry kb7ht uucp: ...sumax!ole!ray CIS: 73407,3152 /* "inquire within" */ On this subject, could anybody post a pinout please ? I've been thinking of using one for a project but can't work out which pins are missing from each independent (?) timer. By my calculation four 555's require a 24pin package, so what's missing ? Kevin -- " If I was someone, I would like to be the fool. ___ No-one would know me and I think that would be cool. " / / )__ __ ^__ __ __-_This_Mortal_Coil ______________________________________/ / ((_(( (((_((_.__
squishy@casbah.acns.nwu.edu (Shishin Yamada) (03/18/91)
>> It's a quad monostable timer chip. Signetics is the (primary) >>source. You might also find an Exar version. >>-- >On this subject, could anybody post a pinout please ? >I've been thinking of using one for a project but can't work out which pins >are missing from each independent (?) timer. >By my calculation four 555's require a 24pin package, so what's missing ? > Output 1 +---+-U-+---+16 Output Timing 2 | A | | D |15 Timing Trigger 3 +---+ +---+14 Trigger Control 4 | |13 Reset Vcc 5 | |12 Ground Trigger 6 +---+ +---+11 Trigger Timing 7 | B | | C |10 Timing Output 8 +---+---+---+9 Output You should view this with a mono-spaced font. The 558 is a 16 pin DIP chip quad version of the 555. It has a common Vcc, Gnd, Reset, and Control pins. For the four timers, called A, B, C, and D, there are only Output, Timing, and Trigger controls for each. Oh yeah, 4.8 < Vcc <18 Volts. Hope that helps! ===================================================== Shishin "Squish" Yamada |\/\/\/| squishy@casbah.acns.nwu.edu /---------\ | | Northwestern University | Yo | (o)(o) | Electrical Engineering | Dudes! \ ( < ) Class of 1991 \__________\ |___/ | \ | "Life sucks, but Death swallows!" / \ /______\ =====================================================