# HG changeset patch # User Paul Boddie # Date 1362934052 -3600 # Node ID fc68c722a834972ff81b48e7bca0d20f4f0ed767 # Parent b0163096b9041f67b4c1fa8bd4b3cd03f64bb20d Improved the assessment of various RAM ICs, adding other product details. Moved references closer to the relevant sections. diff -r b0163096b904 -r fc68c722a834 ULA.txt --- a/ULA.txt Sat Mar 09 23:36:21 2013 +0100 +++ b/ULA.txt Sun Mar 10 17:47:32 2013 +0100 @@ -62,6 +62,11 @@ communicate the latter behaviour. In the TM4164EC4 datasheet, it appears that "page mode" provides the appropriate behaviour for that particular product. +See: Acorn Electron Advanced User Guide +See: Acorn Electron Service Manual + http://acorn.chriswhy.co.uk/docs/Acorn/Manuals/Acorn_ElectronSM.pdf +See: http://mdfs.net/Docs/Comp/Electron/Techinfo.htm + Video Timing ------------ @@ -126,6 +131,15 @@ with approximately 15 blank lines above and below the picture. Thus, the start of the picture could be chosen as 38 lines after the start of vsync. +See: http://en.wikipedia.org/wiki/PAL +See: http://en.wikipedia.org/wiki/Analog_television#Structure_of_a_video_signal +See: The 625/50 PAL Video Signal and TV Compatible Graphics Modes + http://lipas.uwasa.fi/~f76998/video/modes/ +See: PAL TV timing and voltages + http://www.retroleum.co.uk/electronics-articles/pal-tv-timing-and-voltages/ +See: Line Standards + http://www.pembers.freeserve.co.uk/World-TV-Standards/Line-Standards.html + RAM Integrated Circuits ----------------------- @@ -134,39 +148,56 @@ Instruments 4164 chips presumably used in the Electron. The TM4164EC4 series combines 4 64K x 1b units into a single package and -presumably could be used to replace the Electron's separate ICs, but it has 22 +appears similar to the TM4164EA4 featured on the Electron's circuit diagram +(in the Advanced User Guide but not the Service Manual), and it also has 22 pins providing 3 additional inputs and 3 additional outputs over the 16 pins -of the existing modules, presumably allowing concurrent access to the packaged -memory units. +of the individual 4164-15 modules, presumably allowing concurrent access to +the packaged memory units. As far as currently available replacements are concerned, the NTE4164 is a -potential candidate. According to the Vetco Electronics entry, it is -supposedly a replacement for the TMS4164-15 amongst others. Meanwhile, the -NTE21256 appears to be a 16-pin replacement for all four ICs that maintains -the single data input and output pins. +potential candidate: according to the Vetco Electronics entry, it is +supposedly a replacement for the TMS4164-15 amongst many other parts. Similar +parts include the NTE2164 and the NTE6664, both of which appear to have +largely the same performance and connection characteristics. Meanwhile, the +NTE21256 appears to be a 16-pin replacement that with four times the capacity +that maintains the single data input and output pins. Using the NTE21256 as a +replacement for all ICs combined would be difficult because of the single bit +output. -See: Acorn Electron Advanced User Guide -See: http://mdfs.net/Docs/Comp/Electron/Techinfo.htm -See: http://en.wikipedia.org/wiki/PAL -See: http://en.wikipedia.org/wiki/Analog_television#Structure_of_a_video_signal -See: The 625/50 PAL Video Signal and TV Compatible Graphics Modes - http://lipas.uwasa.fi/~f76998/video/modes/ -See: PAL TV timing and voltages - http://www.retroleum.co.uk/electronics-articles/pal-tv-timing-and-voltages/ -See: Line Standards - http://www.pembers.freeserve.co.uk/World-TV-Standards/Line-Standards.html +Another device equivalent to the 4164-15 appears to be available under the +code 41662 from Jameco Electronics as the Siemens HYB 4164-2. The Jameco Web +site lists data sheets for other devices on the same page, but these are +different and actually appear to be provided under the 41574 product code (but +are listed under 41464-10) and appear to be replacements for the TM4164EC4: +the Samsung KM41464A-15 and NEC µPD41464 employ 18 pins, eliminating 4 pins by +employing 4 pins for both input and output. + See: TM4164EC4 65,536 by 4-Bit Dynamic RAM Module http://www.datasheetarchive.com/dl/Datasheets-112/DSAP0051030.pdf See: KM4164B 64K x 1 Bit Dynamic RAM with Page Mode http://images.ihscontent.net/vipimages/VipMasterIC/IC/SAMS/SAMSD020/SAMSD020-45.pdf +See: NTE2164 Integrated Circuit 65,536 X 1 Bit Dynamic Random Access Memory + http://www.vetco.net/catalog/product_info.php?products_id=2806 See: NTE4164 - IC-NMOS 64K DRAM 150NS http://www.vetco.net/catalog/product_info.php?products_id=3680 See: NTE21256 - IC-256K DRAM 150NS http://www.vetco.net/catalog/product_info.php?products_id=2799 See: NTE21256 262,144-Bit Dynamic Random Access Memory (DRAM) http://www.nteinc.com/specs/21000to21999/pdf/nte21256.pdf -See: Acorn Electron Service Manual - http://acorn.chriswhy.co.uk/docs/Acorn/Manuals/Acorn_ElectronSM.pdf +See: NTE6664 - IC-MOS 64K DRAM 150NS + http://www.vetco.net/catalog/product_info.php?products_id=5213 +See: NTE6664 Integrated Circuit 64K-Bit Dynamic RAM + http://www.nteinc.com/specs/6600to6699/pdf/nte6664.pdf +See: 4164-150: MAJOR BRANDS + http://www.jameco.com/webapp/wcs/stores/servlet/Product_10001_10001_41662_-1 +See: HYB 4164-1, HYB 4164-2, HYB 4164-3 65,536-Bit Dynamic Random Access Memory (RAM) + http://www.jameco.com/Jameco/Products/ProdDS/41662SIEMENS.pdf +See: KM41464A NMOS DRAM 64K x 4 Bit Dynamic RAM with Page Mode + http://www.jameco.com/Jameco/Products/ProdDS/41662SAM.pdf +See: NEC µ41464 65,536 x 4-Bit Dynamic NMOS RAM + http://www.jameco.com/Jameco/Products/ProdDS/41662NEC.pdf +See: 41464-10: MAJOR BRANDS + http://www.jameco.com/webapp/wcs/stores/servlet/Product_10001_10001_41574_-1 Interrupts ----------