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Changes for page Front I/O

Last modified by Kevin Wiki on 2024/07/07 22:48
From version 3.2
edited by Kevin Wiki
on 2024/07/04 23:00
Change comment: There is no comment for this version
To version 8.2
edited by Kevin Wiki
on 2024/07/05 14:00
Change comment: There is no comment for this version

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... ... @@ -6,9 +6,14 @@
6 6  
7 7  There is a single cable that controls four parts, each half side of I/O LED and center column of blue LEDs.
8 8  
9 -== ==
9 +[[image:xserve io main cable and PCB pinout.drawio.png||alt="xserve io main cable pinout.drawio.png"]]
10 10  
11 +(% class="wikigeneratedid" %)
12 +[[attach:xserve io main cable and PCB pinout.drawio.svg||target="_blank"]]
11 11  
14 +(% class="wikigeneratedid" %)
15 +This cable allows us to communicate with 4 chips using two data lines, audio & service switch, case switch and (yet to be documented) compute LEDs
16 +
12 12  = How we got here =
13 13  
14 14  Measure out the ground and power signals by comparing with other chips on board. E.g. we find [SAA1064T] datasheet, locate the GND (Vee) and 5V (Vcc) and measure connectivity (0 ohm resistance) between chip pins and cable pins. This gives us pins GND 2 & 8 and PWR 16 & 22.
... ... @@ -143,7 +143,7 @@
143 143  
144 144  == SAA1064T data for driving center IO LED stack ==
145 145  
146 -Center IO stack is a stack of 23 LED's, 22 blue and 1 green for ethernet activity. These are duplicated next to each other and driven by each their SAA1064T chips. Earlier we found the i2c address and just by playing around figured out that 4 segments of 1 byte binary values are used to set ship register.
151 +Center IO stack is a stack of 24 LED's, 23 blue and 1 green for ethernet activity. These are duplicated next to each other and driven by each their SAA1064T chips. Earlier we found the i2c address and just by playing around figured out that 4 segments of 1 byte binary values are used to set ship register.
147 147  
148 148  {{code language="C++"}}
149 149  void fillColumns() {
... ... @@ -161,7 +161,7 @@
161 161  {{/code}}
162 162  
163 163  (% class="wikigeneratedid" %)
164 -Here the last byte we send only is 5 bits since we only have 5 LEDs instead of 6 to address (total of 23). Also note that we start the transmission with a single bit.
169 +~-~- Here the last byte we send only is 5 bits since we only have 5 LEDs instead of 6 to address (total of 24). Also note that we start the transmission with a single bit. ~-~-
165 165  
166 166  == Pinouts voltages from MLB ==
167 167  
... ... @@ -189,6 +189,89 @@
189 189  * Power LED P3V3 - 3.30V
190 190  * Power LED - 0.87 V
191 191  
197 += Controlling top I/O LED =
198 +
199 +On the top row we have the following input/output devices in order from left to right;
200 +
201 +Left side:
202 +
203 +* physical lock
204 +* lock LED
205 +* warning/service button
206 +* warning/service LED
207 +* locate button
208 +* power LED (red & green)
209 +* fan LED (red & green)
210 +* temperature LED (red & green)
211 +* compute LED (unknown)
212 +
213 +Right side:
214 +
215 +* power LED (red & green)
216 +* fan LED (red & green)
217 +* temperature LED (red & green)
218 +* compute LED (unknown)
219 +* lock switch
220 +
221 +Each sides bank of LEDs are driven by each their PCA9554 shift register. The registers represent the following LEDs: (Note that Lock LED is only present for the LEFT side)
222 +
223 +(% border="1" %)
224 +|=(% scope="row" %)Register|1|2|3|4|5|6|7
225 +|=Device|Power LED Green|Power LED Red|Fan LED Green|Fan LED Red|Temperature LED Green|Temperature LED Red|Lock LED
226 +
227 +To control each LED we shift either a 0 to turn off or 1 to turn on. Since each device shares a single red/green LED (power LED green & power LED red) setting both to 1 at the same time will always leave it red. That is when power LED green and power LED red are both enabled, red always takes precedence.
228 +
229 +Use following script to power LEDs one at a time:
230 +
231 +{{code language="c++"}}
232 +#include <PCA9554.h> // Load the PCA9554 Library
233 +
234 +PCA9554 ioCon1(0x24); // Create an object at this address
235 +
236 +uint8_t mapIO = 0b10000000;
237 +
238 +void shiftL() {
239 + mapIO = (mapIO << 1) | ((mapIO & 0x80) >> 7);
240 +}
241 +
242 +void write() {
243 + Serial.println("writing to PCA9554 device");
244 +
245 + for (int i = 0; i < 8; ++i) {
246 + ioCon1.digitalWrite(i, (mapIO & (1 << i)) ? 0 : 1);
247 + }
248 +}
249 +
250 +void setup()
251 +{
252 + Serial.begin(9600);
253 + Serial.println("Setup");
254 +
255 + ioCon1.portMode(ALLOUTPUT);
256 +}
257 +
258 +void loop()
259 +{
260 + write();
261 + shiftL();
262 +
263 + delay(500);
264 +}
265 +{{/code}}
266 +
267 +
268 +Controlling middle IO strip
269 +
270 +0 = 0000
271 +1 (green) = 0001
272 +2 = 0010
273 +1 + 2 = 0011
274 +3 = 0100
275 +
276 +
277 +There are 4 words, each containing 7 data bits. They do not
278 +
279 +
192 192  
193 193  )))
194 194  
xserve io main cable and PCB pinout.drawio.png
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1 +XWiki.kevin
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xserve io main cable and PCB pinout.drawio.svg
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1 +XWiki.kevin
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1 +83.3 KB
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