Docs and syntax

Author: ckormanyos

examples/chapter11_07a/readme.md

@@ -16,7 +16,7 @@ of digits of the mathematical constant $\pi$.
 The spigot-type calculation that was introduced in earlier
 examples is used.
 
-The calculation requires significant RAM,
+The calculations requires considerable amounts of RAM,
 much more than is available on our target system with the $8$--bit microcontroller.
 For this purpose, a $4~\text{MByte}$ external serial SRAM is used.
 This simplifies the breadboard wiring significantly
@@ -29,10 +29,36 @@ An industry-standard display reports the
 progress of the running calculation and the number of
 completed computations in the current power-on cycle.
 
-
 ## Hardware Setup
 
-TODO: The pin connections
+An ARDUINO(R) board is used predominantly out-of-the-box,
+but it has been adapted with manually soldered-on pins allowing
+it to be fitted to the breadboard. The level-shifting is carried out with
+an industry-standard level shifter. The $4~\text{MByte}$ serial SRAM
+is controlled via an all-software SPI channel.
+The LCD display is controlled by a separate independent
+all-software SPI channel.
+
+The pin most important pin connections are shown in the tables below.
+
+### SRAM Connections
+
+| SRAM Pin        | Function   | ARDUINO(R) Connection   |
+| --------------- | ---------- | ----------------------- |
+| 1               | CSN        | portd.7                 |
+| 2               | MISO       | portd.6                 |
+| 6               | SCK        | portd.5                 |
+| 5               | MOSI       | portd.4                 |
+
+
+### LCD Connections
+
+| LCD        | ARDUINO(R) Connection   |
+| ---------- | ----------------------- |
+| CSN        | portb.2                 |
+| SDI        | portd.1                 |
+| SCK        | portd.0                 |
+
 
 TODO: The hardware setup with the $4~\text{MByte}$ serial SRAM
 is pictured in the image below.

examples/chapter11_07a/src/app/pi_calc_cfg.h

@@ -8,6 +8,9 @@
 #ifndef PI_CALC_CFG_2023_05_09_H
   #define PI_CALC_CFG_2023_05_09_H
 
+  // In this embedded software adaptation of this work,
+  // we limit the decimal digit count to about 100k or fewer.
+
   #define PI_CRUNCH_METAL_PI_SPIGOT_USE_100_DIGITS      100
   #define PI_CRUNCH_METAL_PI_SPIGOT_USE_1K_DIGITS      1000
   #define PI_CRUNCH_METAL_PI_SPIGOT_USE_10K_DIGITS    10000

examples/chapter11_07a/src/mcal/avr/mcal_spi_types.h

@@ -9,6 +9,7 @@
   #define MCAL_SPI_TYPES_2024_12_07_H
 
   #include <mcal_port.h>
+  #include <mcal_port_pin_dummy.h>
   #include <mcal_reg.h>
   #include <mcal_spi/mcal_spi_software_port_driver.h>
 
@@ -57,10 +58,7 @@
                                                      mcal::reg::portb,
                                                      static_cast<std::uint32_t>(UINT32_C(2))>;
 
-  using port_pin_lcd_sdo_type = mcal::port::port_pin<std::uint32_t,
-                                                     std::uint32_t,
-                                                     mcal::reg::portb,
-                                                     static_cast<std::uint32_t>(UINT32_C(4))>;
+  using port_pin_lcd_sdo_type = mcal::port::port_pin_dummy;
 
   using port_pin_lcd_sdi_type = mcal::port::port_pin<std::uint32_t,
                                                      std::uint32_t,