Differences

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--- boards:ecb:4pio-i2c:development [2021/04/23 07:05]
b1ackmai1er
+++ boards:ecb:4pio-i2c:development [2023/02/18 23:19] (current)
b1ackmai1er
@@ Line 36: / Line 36: @@
       * Change top layer to vcc plane for better power distribution.
       * Gate /WR with /CS to meet PCF8584 Z80 configuration requirements.
-      * Version C committed including above changes
+      * Version C committed including above changes.
+      * Patches to version B board
+        * Lift pin 1 IC15, connect lifted pin to pin 19 IC13
+        * Lift pin 18 IC16, connect lifted pin 18 to pin 20
+        * Lift pin 5 IC 7, connect pin 6 to pin 15
+        * On solder side connect pin 19 IC13 to pin 2 IC2
+        * On component side, cut track between IC16 pin 17 and IC13 pin 19.
+  * 4PIO-I2Cd
+      * Component placement, routing changes.
+      * Initial ROMWBW HBIOS support.
+      * Add jumper to connect DS1307 battery backup to backplane battery backup.
+      * Add support for 3.3v I2C peripherals using logic level translator.
 ====== Board ======
@@ Line 42: / Line 53: @@
 Kicad files can be found [[https://github.com/b1ackmai1er/ECB-4PIO-I2C|here ]]but may not be the most recent.
-Current revision is ECB-4PIO-I2Cc
+Current revision is ECB-4PIO-I2Cd
 ====== Pictures ======
@@ Line 76: / Line 87: @@
 ====== I2C Addressing ======
-LC512 devices are access on the I2C bus by first issuing a control byte. The control byte consists if a device identifier (D), the device address (A) and a bit (B) to indicate if a read or write operation (O) is intended.
+LC512 devices are access on the I2C bus by first issuing a control byte. The control byte consists of a device identifier (D), the device address (A) and a bit (O) to indicate if a read or write operation is intended.
 So accessing a device requires sending a bye in the following sequence: DDDDAAAO
-__AT25LC512__
+{{:boards:ecb:4pio-i2c:development:24lc512.pdf|AT25LC512}}
 For 24LC512 the device identifier D is 1010, device address is 000-111 and O is set based on a read 1 or write 0.
@@ Line 94: / Line 105: @@
 **Note **that changing the 24LC512 to the alternate address using J1 requires the 1-2 solder link to be cut otherwise a short between +5V and ground will occur.
-__DS1307__
+{{:boards:ecb:4pio-i2c:development:ds1307.pdf|DS1307}}
-For the DS1307 the device identifier D is 1101, device address A is 000 - only one device is supported on the bus, and O is set based on a read 1 or write 0.
+For the DS1307 the device identifier D is 1101, device address A is 000 - only one device is supported on the bus, and O is set based on a read 0 or write 1.
 The control byte for the onboard DS1307 is:
 ^DS1307^DEFAULT|
-^READ|11010001 (D0)|
+^READ|11010000 (D0)|
-^WRITE|11010000 (D1)|
+^WRITE|11010001 (D1)|
+{{:boards:ecb:4pio-i2c:development:pcf8574.pdf|PCF8574}}  > {{:boards:ecb:4pio-i2c:development:hd44780_lcd_driver_datasheet.pdf|LCD}}  {{https://www.retrobrewcomputers.org/lib/exe/fetch.php?tok=0bc8fd&media=https://www.retrobrewcomputers.org/lib/exe/fetch.php?tok=842ba7&media=https://www.retrobrewcomputers.org/lib/exe/fetch.php?tok=100ca2&media=https://www.retrobrewcomputers.org/lib/exe/fetch.php?tok=10f051&media=https://www.retrobrewcomputers.org/lib/exe/fetch.php?tok=5ed9e3&media=https://www.retrobrewcomputers.org/lib/exe/fetch.php?tok=f3f91e&media=https://www.retrobrewcomputers.org/lib/exe/fetch.php?tok=f46157&media=https://www.retrobrewcomputers.org/lib/exe/fetch.php?tok=b40609&media=https://www.retrobrewcomputers.org/lib/exe/fetch.php?media=boards:ecb:4pio-i2c:development:i2c-lcd-backpack.png?linkonly|backpack}}
+A PCF8574 I2C 8-bit I/O expander is commonly used to driver LCD displays.
+For PCF8574 devices, the identifier D is 0100, Up to 8 devices are supported. Backpack boards usually have 3 unbridged solder jumpers giving an address 111 - A. O is set based on a read 1 or write 0.
+The control byte for the onboard DS1307 is:
+^PCF8574^DEFAULT|
+^READ|01001111 (4F)|
+^WRITE|01001110 (4E)|
+====== Software & Drivers ======
+__ROMWBW __
+<code>
+RomWBW HBIOS v3.1.1-pre.75, 2021-05-12
+SBC Z80 @ 12.000MHz
+MEM W/S, 1 I/O W/S, INT MODE 2, SBC MMU
+KB ROM, 512KB RAM
+UART0: IO=0x68 16550A MODE=38400,8,N,1
+I2C: IO=0xF0
+DS1307: 01/01/21 00:00:01
+TMS: IO=0x98 NOT PRESENT
+MD: FLASH=1 1=29F040 FLASH FILE SYSTEM DISABLED
+MD: UNITS=2 ROMDISK=384KB RAMDISK=256KB
+FD: IO=0x36 UNITS=2
+RF: IO=0xA0 WP=OFF IO=0xA4 WP=OFF DEVICES=2
+PPIDE: IO=0x60
+PPIDE0: LBA BLOCKS=0x003DFC20 SIZE=1983MB
+PPIDE1: NO MEDIA
+PPIDE: IO=0x20 PPI NOT PRESENT
+PPIDE: IO=0x44 PPI NOT PRESENT
+</code>
+__Utilities __
+RTCHB - display date and time using HBIOS functions
+<code>
+H>rtchb
+/01/21 00:03:19
+</code>
+RTCDS7 - display date and time using direct access through PCF8584.
+<code>
+H>rtcds7
+/01/21 00:03:35
+</code>
+I2CSCAN - I2C Bus Scanner
+<code>
+H>i2cscan
+I2C Bus Scanner
+01 02 03 04 05 06 07 08 09 0A 0B 0C 0D 0E 0F
+: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
+: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
+: -- -- -- -- -- -- -- 27 -- -- -- -- -- -- -- --
+: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
+: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
+: 50 51 -- -- -- -- -- -- -- -- -- -- -- -- -- --
+: -- -- -- -- -- -- -- -- 68 -- -- -- -- -- -- --
+: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
+</code>
 ====== References ======
@@ Line 115: / Line 201: @@
 Linux C driver: [[https://code.woboq.org/linux/linux/drivers/i2c/algos/i2c-algo-pcf.c.html|https://code.woboq.org/linux/linux/drivers/i2c/algos/i2c-algo-pcf.c.html]]
+I2CScan code: [[https://groups.google.com/group/retro-comp/attach/25120f43d0386/I2CSPI.ZIP?part=0.1|https://groups.google.com/group/retro-comp/attach/25120f43d0386/I2CSPI.ZIP?part=0.1]]
 ====== Key Learnings ======
@@ Line 123: / Line 211: @@
   * Do a hard reset between each software test to ensure consistent results. Exiting in a known state is important.
   * Software control of hard reset is desirable as soft reset does guarantee consistent results.
-\\