1.1 --- a/ULA.txt Sat Mar 09 23:36:21 2013 +0100
1.2 +++ b/ULA.txt Sun Mar 10 17:47:32 2013 +0100
1.3 @@ -62,6 +62,11 @@
1.4 communicate the latter behaviour. In the TM4164EC4 datasheet, it appears that
1.5 "page mode" provides the appropriate behaviour for that particular product.
1.6
1.7 +See: Acorn Electron Advanced User Guide
1.8 +See: Acorn Electron Service Manual
1.9 + http://acorn.chriswhy.co.uk/docs/Acorn/Manuals/Acorn_ElectronSM.pdf
1.10 +See: http://mdfs.net/Docs/Comp/Electron/Techinfo.htm
1.11 +
1.12 Video Timing
1.13 ------------
1.14
1.15 @@ -126,6 +131,15 @@
1.16 with approximately 15 blank lines above and below the picture. Thus, the start
1.17 of the picture could be chosen as 38 lines after the start of vsync.
1.18
1.19 +See: http://en.wikipedia.org/wiki/PAL
1.20 +See: http://en.wikipedia.org/wiki/Analog_television#Structure_of_a_video_signal
1.21 +See: The 625/50 PAL Video Signal and TV Compatible Graphics Modes
1.22 + http://lipas.uwasa.fi/~f76998/video/modes/
1.23 +See: PAL TV timing and voltages
1.24 + http://www.retroleum.co.uk/electronics-articles/pal-tv-timing-and-voltages/
1.25 +See: Line Standards
1.26 + http://www.pembers.freeserve.co.uk/World-TV-Standards/Line-Standards.html
1.27 +
1.28 RAM Integrated Circuits
1.29 -----------------------
1.30
1.31 @@ -134,39 +148,56 @@
1.32 Instruments 4164 chips presumably used in the Electron.
1.33
1.34 The TM4164EC4 series combines 4 64K x 1b units into a single package and
1.35 -presumably could be used to replace the Electron's separate ICs, but it has 22
1.36 +appears similar to the TM4164EA4 featured on the Electron's circuit diagram
1.37 +(in the Advanced User Guide but not the Service Manual), and it also has 22
1.38 pins providing 3 additional inputs and 3 additional outputs over the 16 pins
1.39 -of the existing modules, presumably allowing concurrent access to the packaged
1.40 -memory units.
1.41 +of the individual 4164-15 modules, presumably allowing concurrent access to
1.42 +the packaged memory units.
1.43
1.44 As far as currently available replacements are concerned, the NTE4164 is a
1.45 -potential candidate. According to the Vetco Electronics entry, it is
1.46 -supposedly a replacement for the TMS4164-15 amongst others. Meanwhile, the
1.47 -NTE21256 appears to be a 16-pin replacement for all four ICs that maintains
1.48 -the single data input and output pins.
1.49 +potential candidate: according to the Vetco Electronics entry, it is
1.50 +supposedly a replacement for the TMS4164-15 amongst many other parts. Similar
1.51 +parts include the NTE2164 and the NTE6664, both of which appear to have
1.52 +largely the same performance and connection characteristics. Meanwhile, the
1.53 +NTE21256 appears to be a 16-pin replacement that with four times the capacity
1.54 +that maintains the single data input and output pins. Using the NTE21256 as a
1.55 +replacement for all ICs combined would be difficult because of the single bit
1.56 +output.
1.57
1.58 -See: Acorn Electron Advanced User Guide
1.59 -See: http://mdfs.net/Docs/Comp/Electron/Techinfo.htm
1.60 -See: http://en.wikipedia.org/wiki/PAL
1.61 -See: http://en.wikipedia.org/wiki/Analog_television#Structure_of_a_video_signal
1.62 -See: The 625/50 PAL Video Signal and TV Compatible Graphics Modes
1.63 - http://lipas.uwasa.fi/~f76998/video/modes/
1.64 -See: PAL TV timing and voltages
1.65 - http://www.retroleum.co.uk/electronics-articles/pal-tv-timing-and-voltages/
1.66 -See: Line Standards
1.67 - http://www.pembers.freeserve.co.uk/World-TV-Standards/Line-Standards.html
1.68 +Another device equivalent to the 4164-15 appears to be available under the
1.69 +code 41662 from Jameco Electronics as the Siemens HYB 4164-2. The Jameco Web
1.70 +site lists data sheets for other devices on the same page, but these are
1.71 +different and actually appear to be provided under the 41574 product code (but
1.72 +are listed under 41464-10) and appear to be replacements for the TM4164EC4:
1.73 +the Samsung KM41464A-15 and NEC µPD41464 employ 18 pins, eliminating 4 pins by
1.74 +employing 4 pins for both input and output.
1.75 +
1.76 See: TM4164EC4 65,536 by 4-Bit Dynamic RAM Module
1.77 http://www.datasheetarchive.com/dl/Datasheets-112/DSAP0051030.pdf
1.78 See: KM4164B 64K x 1 Bit Dynamic RAM with Page Mode
1.79 http://images.ihscontent.net/vipimages/VipMasterIC/IC/SAMS/SAMSD020/SAMSD020-45.pdf
1.80 +See: NTE2164 Integrated Circuit 65,536 X 1 Bit Dynamic Random Access Memory
1.81 + http://www.vetco.net/catalog/product_info.php?products_id=2806
1.82 See: NTE4164 - IC-NMOS 64K DRAM 150NS
1.83 http://www.vetco.net/catalog/product_info.php?products_id=3680
1.84 See: NTE21256 - IC-256K DRAM 150NS
1.85 http://www.vetco.net/catalog/product_info.php?products_id=2799
1.86 See: NTE21256 262,144-Bit Dynamic Random Access Memory (DRAM)
1.87 http://www.nteinc.com/specs/21000to21999/pdf/nte21256.pdf
1.88 -See: Acorn Electron Service Manual
1.89 - http://acorn.chriswhy.co.uk/docs/Acorn/Manuals/Acorn_ElectronSM.pdf
1.90 +See: NTE6664 - IC-MOS 64K DRAM 150NS
1.91 + http://www.vetco.net/catalog/product_info.php?products_id=5213
1.92 +See: NTE6664 Integrated Circuit 64K-Bit Dynamic RAM
1.93 + http://www.nteinc.com/specs/6600to6699/pdf/nte6664.pdf
1.94 +See: 4164-150: MAJOR BRANDS
1.95 + http://www.jameco.com/webapp/wcs/stores/servlet/Product_10001_10001_41662_-1
1.96 +See: HYB 4164-1, HYB 4164-2, HYB 4164-3 65,536-Bit Dynamic Random Access Memory (RAM)
1.97 + http://www.jameco.com/Jameco/Products/ProdDS/41662SIEMENS.pdf
1.98 +See: KM41464A NMOS DRAM 64K x 4 Bit Dynamic RAM with Page Mode
1.99 + http://www.jameco.com/Jameco/Products/ProdDS/41662SAM.pdf
1.100 +See: NEC µ41464 65,536 x 4-Bit Dynamic NMOS RAM
1.101 + http://www.jameco.com/Jameco/Products/ProdDS/41662NEC.pdf
1.102 +See: 41464-10: MAJOR BRANDS
1.103 + http://www.jameco.com/webapp/wcs/stores/servlet/Product_10001_10001_41574_-1
1.104
1.105 Interrupts
1.106 ----------
