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SiriusHardware · 28th Mar 2021, 12:44 am

If anyone does have a programmer which can 'do' the Texas SN74S287 then it might be possible to programme an MH74S571 in two passes, with a slight adaptation.

The difference between the two is pin 14 (CE2 on 287, A8 on 571). You could tie pin 14 low to programme the lower 256 nibbles, and then tie pin 14 high to programme the upper 256 nibbles, both times with the programmer set to programme the 256 x 4-bit SN74S287.

Unfortunately my programmer does not offer the SN74S287 either, so I can't try it.

28th Mar 2021, 12:44 am	#281
SiriusHardware Dekatron Join Date: Aug 2011 Location: Newcastle, Tyne and Wear, UK. Posts: 11,556	Re: I found it! A very sorry looking MK14. If anyone does have a programmer which can 'do' the Texas SN74S287 then it might be possible to programme an MH74S571 in two passes, with a slight adaptation. The difference between the two is pin 14 (CE2 on 287, A8 on 571). You could tie pin 14 low to programme the lower 256 nibbles, and then tie pin 14 high to programme the upper 256 nibbles, both times with the programmer set to programme the 256 x 4-bit SN74S287. Unfortunately my programmer does not offer the SN74S287 either, so I can't try it.