Index: docs/ecn/STATUS =================================================================== --- docs/ecn/STATUS (revision 5604) +++ docs/ecn/STATUS (working copy) @@ -38,6 +38,7 @@ 0036 Discuss Removal of decoupling capacitor C3020 0037 Discuss Route ROUT1/LOUT1 back to LINE1/LINE2 input 0038 Discuss Loudspeaker EMI filter +0039 Discuss Insert 0R resistors into SPI signals Open ECNs --------- @@ -62,3 +63,4 @@ 0036 AUDIO 0037 AUDIO 0038 AUDIO +0039 CPU, LCM
--- /dev/null 2009-08-16 19:25:44.824052888 +0200 +++ docs/ecn/ecn0039.txt 2009-09-05 19:37:09.000000000 +0200 @@ -0,0 +1,33 @@ +Insert 0R resistors into SPI signals + + +The SC32442B SPI interface running at 13 MHz or faster has timing problems[1] +that we might need to patch up externally. Following ECN0001 (Glamo removal) +and ECN0034 the SPI interface exposed at the debug connector will now be routed +to the alternative SPI1 pins of the LCD interface. There is some uncertainty +about the SPICLK1 signal there[2]. Finally, the SPI1 pins currently routed to the +accelerometer have EINT capability while the debug connector ones do not, so to +make better use of EINT pins, we should find out if the two sets of SPI pins can +be swapped. + +The change is to insert a 0R resistor into all the SPI signals: + +SPICLK0/GPE13 +SPIMOSI0/GPE12 +SPIMISO0/GPE11 +EINT11/nSS1/GPG3 +EINT13/SPIMISO1/GPG5 +EINT14/SPIMOSI1/GPG6 +EINT15/SPICLK1/GPG7 +VD9/SPICLK1/GPD1 +VD17/SPIMOSI1/GPD9 +VD16/SPIMISO1/GPD8 + +Impact: We won't likely have enough 0R resistors supplied by OM and therefore +need to buy some. + +[1] https://lists.openmoko.org/pipermail/openmoko-kernel/2008-September/005261.html +[2] https://lists.openmoko.org/pipermail/gta03/2009-May/000210.html + + +Author: Rask Ingemann Lambertsen <[email protected]> -- Rask Ingemann Lambertsen Danish law requires addresses in e-mail to be logged and stored for a year _______________________________________________ gta02-core mailing list [email protected] https://lists.openmoko.org/mailman/listinfo/gta02-core
